CA2374854C - Random access control method and system - Google Patents
Random access control method and system Download PDFInfo
- Publication number
- CA2374854C CA2374854C CA002374854A CA2374854A CA2374854C CA 2374854 C CA2374854 C CA 2374854C CA 002374854 A CA002374854 A CA 002374854A CA 2374854 A CA2374854 A CA 2374854A CA 2374854 C CA2374854 C CA 2374854C
- Authority
- CA
- Canada
- Prior art keywords
- parameter
- allowed
- access
- random access
- slots
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W74/00—Wireless channel access, e.g. scheduled or random access
- H04W74/002—Transmission of channel access control information
- H04W74/006—Transmission of channel access control information in the downlink, i.e. towards the terminal
Abstract
The present invention relates to a method and system for performing a random access operation between a mobile station and a network element such as a base transceiver station (10), wherein allowed access slots for random access channels are defined by the network and are signaled to the mobile station (20). The definition of the allowed access slots is performed on the basis of a parameter set by the base transceiver station (10) and transmitted to the mobile station (20) which determines the allowed access slots based on the parameter. Thus, the number of allowed access slots can be defined by the network and can be changed dynamically based on the random access messaging load and the hardware requirements.
Description
RANDOM ACCESS CONTROL METHOD AND SYSTEM
FIELD OF THE INVENTION
The present invention relates to a method and system for performing random access in a mobile communication network comprising a base transceiver station and a mobile station, such as a radio access network of a WCDMA (Wideband Code Division Multiple Access) system like the UMTS (Universal Mobile Telecommunications System).
BACKGROUND OF THE INVENTION
WCDMA has been chosen as the radio technology for the paired bands of the UMTS. Consequently, WCDMA is a common radio technology standard for third-generation wide-area mobile communications.
A fast and efficient random access procedure has been defined in the WCDMA system, wherein random access is based on a slotted Aloha transmission of a random access burst.
The burst contains a preamble part, where a cell specific preamble code is used to transmit a preamble sequence randomly picked by the mobile station. The preamble sequence is detected in the receiver using a matched filter, and specifies a subset of a code tree that defines the channelization code (short code) used for an RACH
(Random Access CHannel) message part.
In particular, a random access communication between a mobile station and the base transceiver station is established by means of an uplink PRACH (Physical Random Access Channel) and a downlink AICH (Acquisition Indication Channel), wherein the PRACH carries a RACH (Random Access
FIELD OF THE INVENTION
The present invention relates to a method and system for performing random access in a mobile communication network comprising a base transceiver station and a mobile station, such as a radio access network of a WCDMA (Wideband Code Division Multiple Access) system like the UMTS (Universal Mobile Telecommunications System).
BACKGROUND OF THE INVENTION
WCDMA has been chosen as the radio technology for the paired bands of the UMTS. Consequently, WCDMA is a common radio technology standard for third-generation wide-area mobile communications.
A fast and efficient random access procedure has been defined in the WCDMA system, wherein random access is based on a slotted Aloha transmission of a random access burst.
The burst contains a preamble part, where a cell specific preamble code is used to transmit a preamble sequence randomly picked by the mobile station. The preamble sequence is detected in the receiver using a matched filter, and specifies a subset of a code tree that defines the channelization code (short code) used for an RACH
(Random Access CHannel) message part.
In particular, a random access communication between a mobile station and the base transceiver station is established by means of an uplink PRACH (Physical Random Access Channel) and a downlink AICH (Acquisition Indication Channel), wherein the PRACH carries a RACH (Random Access
2 Channel) through which the mobile station communicates with the base transceiver station. The mobile station transmits a random access message to the base transceiver station via the RACH when it wants to initiate a dedicated channel for e.g. a speech connection or it has some packet data which are to be transmitted. The base transceiver station transmits acknowledgments of RACH preamble signatures to the mobile station on the AICH, according to which the RACH
message transmission is started.
However, in the common proposals for the WCDMA system, only a subset of all possible PRACH and AICH access slots is used, which limits the capacity of the RACH. This is not desirable especially in cases of high network loads.
Moreover, the number of access slots of the PRACH and the AICH is low. A preamble and an acquisition indicator (AI) may be transmitted every third or fourth access slot, so that the amount of hardware resources to be allocated to the RACH reception is low. If a single PRACH with such a limited capacity is not sufficient for a random access procedure, several PRACH and AICH channels per cell of the base transceiver station have to be configured. This leads to an undesirable complex random access procedure.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a random access method and system, which enable a more flexible use of the random access channels.
This object is achieved by a method for performing random access in a mobile communication network having a base
message transmission is started.
However, in the common proposals for the WCDMA system, only a subset of all possible PRACH and AICH access slots is used, which limits the capacity of the RACH. This is not desirable especially in cases of high network loads.
Moreover, the number of access slots of the PRACH and the AICH is low. A preamble and an acquisition indicator (AI) may be transmitted every third or fourth access slot, so that the amount of hardware resources to be allocated to the RACH reception is low. If a single PRACH with such a limited capacity is not sufficient for a random access procedure, several PRACH and AICH channels per cell of the base transceiver station have to be configured. This leads to an undesirable complex random access procedure.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a random access method and system, which enable a more flexible use of the random access channels.
This object is achieved by a method for performing random access in a mobile communication network having a base
- 3 -transceiver station and a plurality of mobile stations, comprising the steps of:
transmitting a parameter defining allowed uplink access slots from the base transceiver station to a mobile station;
determining said allowed uplink access slots at the mobile station based on the parameter; and using at least one of the determined allowed uplink access slots for performing a random access operation to the base transceiver station.
Furthermore, the above object is achieved by a system for performing random access in a mobile communication network, comprising:
a network element arranged for transmitting a parameter defining allowed uplink access slots; and a plurality of mobile stations arranged for receiving the transmitted parameter, for determining the allowed uplink access slots based on the received parameter, and for using at least one of the determined allowed uplink access slots for performing a random access to the base transceiver station.
Additionally, the above object is achieved by a network element for a mobile communication network comprising a plurality of mobile stations, comprising:
setting means for setting a parameter defining allowed uplink access slots for performing a random access operation; and transmitting means for transmitting the parameter to the plurality of mobile stations.
In addition thereto, the above object is achieved by a mobile station for a mobile communication network having at
transmitting a parameter defining allowed uplink access slots from the base transceiver station to a mobile station;
determining said allowed uplink access slots at the mobile station based on the parameter; and using at least one of the determined allowed uplink access slots for performing a random access operation to the base transceiver station.
Furthermore, the above object is achieved by a system for performing random access in a mobile communication network, comprising:
a network element arranged for transmitting a parameter defining allowed uplink access slots; and a plurality of mobile stations arranged for receiving the transmitted parameter, for determining the allowed uplink access slots based on the received parameter, and for using at least one of the determined allowed uplink access slots for performing a random access to the base transceiver station.
Additionally, the above object is achieved by a network element for a mobile communication network comprising a plurality of mobile stations, comprising:
setting means for setting a parameter defining allowed uplink access slots for performing a random access operation; and transmitting means for transmitting the parameter to the plurality of mobile stations.
In addition thereto, the above object is achieved by a mobile station for a mobile communication network having at
- 4 -least one network element allowing a random access operation, comprising:
receiving means for receiving from the network element a parameter defining allowed uplink access slots for the random access operation;
determining means for determining the allowed uplink access slots based on the received parameter; and transmitting means for transmitting a random access message to the network element using at least one of the determined allowed uplink access slots.
Accordingly, the allowed access slots of the random access channels can be defined and signaled to the mobile stations. The same algorithms can be used by the mobile station and the base transceiver station to determine the access slots in which the transmission or reception can be performed, based on required parameters. Thus, the number of allowed access slots can be defined by the network and may be changed even dynamically based on the random access messaging load or hardware parameters.
According to the invention, the number of allowed access slots of the random access channels can be configured to match more closely the requirements of the random access communication. Since the network defines the allowed access slots, hardware resources of the base transceiver station can be taken into account when deciding on the number of allowed access slots. The selection of the uplink access slots for each preamble transmission can be randomized, to thereby reduce preamble collisions. Since the number of allowed access slots for the random access channels is a network-specific variable, the amount of base transceiver station resources which must be allocated to random access reception and transmission may change dynamically.
Preferably, the parameter is transmitted via a broadcast channel, such as the BCH channel of the WCDMA system. The random access may be performed via the PRACH uplink channel
receiving means for receiving from the network element a parameter defining allowed uplink access slots for the random access operation;
determining means for determining the allowed uplink access slots based on the received parameter; and transmitting means for transmitting a random access message to the network element using at least one of the determined allowed uplink access slots.
Accordingly, the allowed access slots of the random access channels can be defined and signaled to the mobile stations. The same algorithms can be used by the mobile station and the base transceiver station to determine the access slots in which the transmission or reception can be performed, based on required parameters. Thus, the number of allowed access slots can be defined by the network and may be changed even dynamically based on the random access messaging load or hardware parameters.
According to the invention, the number of allowed access slots of the random access channels can be configured to match more closely the requirements of the random access communication. Since the network defines the allowed access slots, hardware resources of the base transceiver station can be taken into account when deciding on the number of allowed access slots. The selection of the uplink access slots for each preamble transmission can be randomized, to thereby reduce preamble collisions. Since the number of allowed access slots for the random access channels is a network-specific variable, the amount of base transceiver station resources which must be allocated to random access reception and transmission may change dynamically.
Preferably, the parameter is transmitted via a broadcast channel, such as the BCH channel of the WCDMA system. The random access may be performed via the PRACH uplink channel
5 and the AICH downlink channel.
The parameter may define a subset of available access slots of the mobile communication network. The subset may be determined by another parameter transmitted from the base transceiver station to the mobile station, wherein the other parameter can be a timing parameter defining a transmission timing of an uplink access slot. The other parameter may also be transmitted via the broadcast channel. Preferably, the bit number of the parameter may be changed in dependence on the other parameter.
A transmission of a preamble signature or an acquisition indication may be disabled in dependence of the value of the parameter.
Furthermore, an index of an allowed uplink access slot may be calculated on the basis of the value of the parameter and a frame number of a frame used for transmitting an uplink access slot. In this case, the parameter may determine an offset to be added to the calculated index.
The allowed downlink slots may be determined by adding a predetermined value to an index of a received uplink slot.
In this case, the predetermined value may depend on a timing parameter defining a transmission timing of the uplink slot.
Alternatively, an index of an allowed uplink access slot may be determined on the basis of the value of the
The parameter may define a subset of available access slots of the mobile communication network. The subset may be determined by another parameter transmitted from the base transceiver station to the mobile station, wherein the other parameter can be a timing parameter defining a transmission timing of an uplink access slot. The other parameter may also be transmitted via the broadcast channel. Preferably, the bit number of the parameter may be changed in dependence on the other parameter.
A transmission of a preamble signature or an acquisition indication may be disabled in dependence of the value of the parameter.
Furthermore, an index of an allowed uplink access slot may be calculated on the basis of the value of the parameter and a frame number of a frame used for transmitting an uplink access slot. In this case, the parameter may determine an offset to be added to the calculated index.
The allowed downlink slots may be determined by adding a predetermined value to an index of a received uplink slot.
In this case, the predetermined value may depend on a timing parameter defining a transmission timing of the uplink slot.
Alternatively, an index of an allowed uplink access slot may be determined on the basis of the value of the
6 PCT/EP99/03630 parameter irrespective of a frame number of a frame used for transmitting an uplink access slot.
Additionally, the binary configuration of the parameter may determine a combination of calculated indices obtained for other values of the parameter, wherein the other values corresponds to the binary weights of the binary configuration.
The base transceiver station may comprise a transmitting means arranged for transmitting the parameter via the broadcast channel.
Furthermore, the setting means may be arranged to set the parameter in dependence on the timing parameter value defining a transmission timing of an uplink access slot in the random access operation.
Additionally, the determining means of the mobile station may be arranged to determine the allowed uplink access slots on the basis of the received parameter and the timing parameter. In particular, determining means may be arranged to calculate an index of an allowed uplink access slot on the basis of the value of the received parameter and a frame number of a frame used for transmitting an uplink access slot. Alternatively, the determining means may be arranged to determine an index of an allowed uplink access slot on the basis of the value of the parameter irrespective of a frame number of a frame used for transmitting an uplink access slot.
Preferably, a selection means is provided in the mobile station for randomly selecting from allowed access slots determined by the determining means an uplink access slot
Additionally, the binary configuration of the parameter may determine a combination of calculated indices obtained for other values of the parameter, wherein the other values corresponds to the binary weights of the binary configuration.
The base transceiver station may comprise a transmitting means arranged for transmitting the parameter via the broadcast channel.
Furthermore, the setting means may be arranged to set the parameter in dependence on the timing parameter value defining a transmission timing of an uplink access slot in the random access operation.
Additionally, the determining means of the mobile station may be arranged to determine the allowed uplink access slots on the basis of the received parameter and the timing parameter. In particular, determining means may be arranged to calculate an index of an allowed uplink access slot on the basis of the value of the received parameter and a frame number of a frame used for transmitting an uplink access slot. Alternatively, the determining means may be arranged to determine an index of an allowed uplink access slot on the basis of the value of the parameter irrespective of a frame number of a frame used for transmitting an uplink access slot.
Preferably, a selection means is provided in the mobile station for randomly selecting from allowed access slots determined by the determining means an uplink access slot
- 7 -to be used for transmitting a preamble of said random access message. In this case, the consecutive preambles may be transmitted a predetermined number of access slots apart. The predetermined number may depend on a timing parameter received by said receiving means. Alternatively, the selection means may be arranged to perform the random selection any time a preamble needs to be transmitted.
According to a further broad aspect of the present invention there is provided a method for performing random access in a mobile communication network having a base transceiver station and a plurality of mobile stations. The method comprises the steps of transmitting a parameter defining allowed access slots of at least one physically existing random access channel to said mobile station;
determining said allowed access slots at said mobile station based on said parameter; and using at least one of said determined allowed access slots for performing a ran access operation to said base transceiver station.
According to a further broad aspect of the present invention there is provided a system for performing random access in a mobile communication network. The system comprises a network element arranged for transmitting a parameter defining allowed access slots of at least one physically existing random access channel; and a plurality of mobile stations arranged for receiving said transmitted parameter, for determining said allowed access slots based on said received parameter, and for using at least one of said determined allowed access slots for performing a random access operation to said base transceiver station.
According to a still further broad aspect of the present invention there is provided a network element for a mobile communication network comprising a plurality of mobile - 7a -stations. The network element comprises setting means for setting a parameter defining allowed access slots of at least one physically existing random access channel for performing a random access operation; and transmitting means for transmitting said parameter to said plurality of mobile stations.
According to a still further broad aspect of the present invention there is provided a mobile station for a mobile communication network having at least one network element allowing a random access operation. The mobile station comprises receiving means for receiving a parameter defining allowed access slots of at least one physically existing random access channel for said random access operation from said network element; determining means for determining said allowed access slots based on said received parameter; and transmitting means for transmitting a random access message to said network element using at least one of said determined allowed access slots.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the present invention will be described in greater detail on the basis of a preferred embodiment with reference to the accompanying drawings, in which:
Fig. 1 shows a random access timing used in a random access channel according to a first example of the preferred embodiment of the present invention;
Fig. 2 shows a principle block diagram of a base transceiver station and a mobile station according to the preferred embodiment of the present invention ;
- 7b -Fig. 3 shows a table indicating a relationship between allowed access slots, a radio frame index and received parameters, according to a first example of the preferred embodiment of the present invention;
Fig. 4 shows a table indicating a relationship between allowed access slots and received parameters according to the first example of the preferred embodiment of the present invention;
- $ -Fig. 5 shows a table indicating a relationship between allowed access slots and received parameters according to a second example of the preferred embodiment of the present invention; and Fig. 6 shows a table indicating a relationship between allowed access slots, a radio frame index and received parameters, according to the second example of the preferred embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, the preferred embodiment of the method and system according to the present invention will be described on the basis of a WCDMA system.
Before a mobile station (MS) can start transmitting on the PRACH channel, it needs to acquire several parameters by decoding a message broadcast from a base transceiver station (BTS) via the Broadcast Channel (BCH). In particular, the MS needs to know e.g. the available access slots of the PRACH and AICH channels and the AICH
transmission timing parameter TAICH= These parameters must also be known at a layer 1 transceiver of the BTS, so that a PRACH reception and a AICH transmission can be performed.
According to the preferred embodiment of the present invention, the MS or a BTS can derive the available access slots on the basis of a parameter A transmitted via the BCH. Thus, the allowed access slots are defined on the basis of the parameters A and TAICH. However, the present invention is not restricted thereto, i.e. the allowed access slots may as well be defined solely on the basis of the parameter A alone.
After the allowed access slots have been determined at the MS, the MS selects an access slot in which a preamble signature will be transmitted.
[First example]
Fig. 1 shows a first example of a possible timing configuration of the random access channels. In this case, a radio frame of the random access channels has a length of 10 ms, wherein both uplink and downlink access slots have a length of 1.25 ms, such that each radio frame comprises eight access slots which can be allowed for the random access operation. For each uplink access slot, a corresponding downlink access slot is provided. Preambles and AIs are transmitted in time alignment with the uplink and downlink access slots, respectively. An uplink access slot is transmitted a specified time period before the corresponding downlink access slot. This ti,,r~e period is equal to 1.75 ms or 3 ms for TAICH = 0 and TAICH = 1, respectively.
However, the present invention is not restricted to the above timing. Any other timing scheme, such as 15 access slots per 20 ms according to the second example described later, could be implemented as well.
The RACH message can be transmitted either three or four access slots after the latest transmitted preamble, depending on the value of TAZCx. The timing offset between uplink and downlink access slots, as seen from the MS, is equal to 0.5 ms. Therefore, an access slot starts 0.5 ms earlier in the uplink direction as compared to the downlink direction.
According to Fig. 1, the access slots in each frame F are denoted by indices 0 to 7, and the radio frames F are numbered from 0 to (NF-1), wherein NF denotes the number of available radio frames indices. In the above alternative case of e.g. 15 access slots per 20ms (not shown), the access slots are denoted by indices 0 to 14.
In general, NF must be an integer number large enough to enable a selection combining in a switching means such as a radio network controller (RNC). This can be achieved, if NF
satisfies the following conditions:
(NF - 1) modulo 3 = 2, and (NF/2 - 1) modulo 4 = 3 Fig. 2 shows a principle block diagram of a BTS 10 and an MS 20 according to the preferred embodiment of the present invention.
The BTS 10 comprises a transceiver (TRX) 11 for receiving and transmitting messages via corresponding radio channels to the MS 20. Furthermore, the BTS 10 comprises a parameter setting unit 14 in which random access parameters such as the parameter A and the timing parameter TAICH are set. The setting may be controlled by the BTS 10 or on the basis of an external command received from the mobile network.
The parameter setting unit 14 is connected to a random access (RAC) control unit 15 for performing a signal processing required for the random access operations via the BCH and AICH channels. Based on the parameters received from the parameter setting unit 14 the RAC control unit 15 supplies a corresponding broadcast message to the TRX 11 which transmits the broadcast message to MSs located in the corresponding radio cell controlled by the BTS 10.
Furthermore, the RAC control unit 15 is connected to a switch 13 by means of which a connection to another network element such as a radio network controller (RNC) can be established in order to receive e.g. a control command for externally controlling the parameter setting unit 14.
In case the BTS 10 receives a random access message from the MS 20 via the PRACH channel, the TRX 11 supplies the received message to a slot determination unit 12 arranged to detect an index of the uplink access slot selected by the MS 20 from the allowed access slots defined by the parameters A and TAICH. Based on the detected index of the received uplink access slot, the slot determination unit 12 determines indices of allowed downlink slots of the AICH
channel, to be used for transmitting a response message to the MS 20. The determination of the indices of the allowed downlink access slots is performed on the basis of an algorithm described later.
Additionally, the slot determination unit 12 is connected to the switch 13 in order to supply received random access messages to the network.
The MS 20 comprises a TRX 21 for transmitting and receiving messages via corresponding radio channels. The TRX 21 is connected to a parameter extraction unit 22, where the random access parameters such as the parameter A and the parameter TAICH are extracted from the BCH channel. The extracted parameters are supplied to a slot determination unit 23 arranged to determine the allowed uplink access slots based on a predefined algorithm which may depend on the value of the parameter TAICH and which is described later. The determined allowed access slots are supplied to a slot selection unit 24 in which at least one desired uplink access slot is selected. The uplink access slot may be selected randomly based on the determined allowed access slots. Once the selection is done, consecutive preambles are transmitted either three or four access slots apart, depending on the value of the parameter TAICH=
Alternatively, the MS 20 may randomly select a number which defines a subset of the determined allowed access slots, which the MS 20 will then use for transmitting the random access message.
The index of the selected access slot is supplied to a random access (RAC) control unit 25 arranged for performing a signal processing required for the random access operations via the PRACH channel. The RAC control unit 25 generates a random access message based on an information supplied from an I/0 unit 27 via a signal processing unit 26 to the TRX 21, in order to be transmitted via the PRACH
channel to the BTS 10. The signal processing unit 26 is provided for performing the required base band signaling of any input or output signal exchanged between the RAC
control unit 25 and the I/O unit 27.
In the following, algorithms used by the slot determining unit 23 and the RAC control unit 15 for determining allowed uplink and, respectively, downlink access slots based on the parameters A and TAICH are described with reference to Figures 3 and 4.
As already mentioned, each radio frame F may contain eight access slots each having a respective index a, wherein 0 s a s 7. The index of the radio frame F ranges between 0 and (NF-1). Alternatively, two consecutive radio frames 2=F and 2=F+l which form a 20 ms frame I' may contain fifteen access slots, i.e. 0 s a s 14.
Initially, the network, e.g. the BTS 10, informs the mobile stations, located within the covered radio area, of the available access slots of the PRACH and AICH channel by transmitting the parameters TAICH and A in the BCH channel, wherein TAICH may be equal to 0 or 1. In case TAICH = 0, the value of A may range between 0 and 7 (i.e. 0 s A s 7, or 000 s A s 111 in binary expression). In case the value of TAICH equals to 1, the values of the parameter A may range between 0 and 15 (i.e. 0 s A s 15, or 0000 s A s 1111 in binary expression).
According to the preferred embodiment, each bit of the binary expression of the parameter A indicates either an inclusion or an exclusion of a subset of access slots to the set of allowed access slots.
Fig. 3 shows a table indicating allowed subsets of access slots in dependence on the parameter A and the frame index F, in case the value of the parameter TAICH equals to 0.
In case A is equal to 0 (000 in binary expression), the transmission of a preamble signature or an AI is forbidden or disabled in all access slots, since each bit of the binary expression is 0.
When A equals to 1 (001 in binary expression), the indices of the allowed uplink access slots in any radio frame F are obtained by the equation:
i = 3- N + (F modulo 3) where 0 s N s 2, wherein N is an integer number and i denotes the index of the allowed access slot, wherein only access slots having indices within the range 0 to 7 are valid. Based on the above equation, the values indicated in the column A = 1 of the table shown in Fig. 3 are obtained.
Since each bit of the parameter A indicates either an inclusion or exclusion of a subset of access slots, the subsets are defined by A = 1 (001), A = 2 (010) and A = 4 (100), which reflect the binary weights of the binary expression.
Basically, the subsets for A = 2 are obtained by increasing the indices of the subsets for A = 1 by one, wherein the value 8 is deleted and transferred as a value 0 to the next radio frame F+1. Similarly, the subset of allowed access slots for A = 4 is obtained from the subset for A = 2 by increasing the indices by one and transferring an obtained value 8 as a value 0 to the subsequent radio frame. Thus, an offset added to a basic subset (A = 1) is determined by the value of the parameter A.
The other sets of allowed access slots for the remaining values of the parameter A can be determined by adding respective ones of the subsets given in the table of Fig. 3 based on the bit values in the binary expression of the parameter A. E.g., in case the parameter A equals to 7 having the binary expression 111 and thus including all binary weights, the subsets for A = 1, A = 2 and A = 4 are all included in the set of allowed access slots, which leads to the maximum allowable slot number. Furthermore, in case A equals to 5 having the binary expression 101, the subsets defined by A = 1 and A = 4 are added to obtain the set of allowed access slots, and so on.
In the following, an index of an access slot is denoted by a pair (F, a), wherein F (0 s F s(NF-1)) denotes the frame index and a (0 s a s 7) denotes the access slot index (within a frame F). E.g., the allowed access slots for A
1 and F = 0, shown in Fig. 3, can be expressed as (0,0) (0,3) and (0, 6) .
(Flu, alu)0 denotes any uplink access slot for A = 1 and TAICH = 0. The corresponding downlink access slots determined by the slot determination unit 12 of the BTS 10 are given by (Fld, ald)0, wherein Fld =(Flu + ald/8) modulo NF and ald =(alu + 1) modulo 8 in the above case of eight access slots per radio frame. In the equation for Fld õ/" stands for an integer division, i.e. truncation. Thus, in general, a downlink access slot is given by (Fxd, axd)0 =(Fxuaxu)0 + 1, for A = x and TAICH = 0-Accordingly, when A equals to 2 (010 in binary expression), the allowed uplink access slots are defined by (F2u, a2u) 0 =(Flu, alu) 0 + 1. Similarly, (F4u, a4u)0 =
(F2u, a2u)0 + 1.
Due to the modulo 3 operation for the frame index F, the allowed access slots are changed over three consecutive radio frames. The reason therefore is that the cycle of the PRACH access slot timing is 30 ms, which corresponds to three radio frames.
Fig. 4 shows a table indicating the relationship between the allowed access slots and the parameter A in case the value of TAICH = 1=
In this case, the allowed access slots are equal in any radio frame, i.e. the determination is performed irrespective of the frame index F. This is due to the fact that the cycle of the PRACH access slot timing is one radio frame if TAICH = 1=
When TAICH = 1, the parameter A ranges between 0 and 15, i.e. comprises four bits in the binary expression.
Therefore, four different sets of allowed access slots are defined, wherein each bit of the parameter A indicates either an inclusion or exclusion of the corresponding set of allowed access slots.
When A equals to 0 (0000 in binary expression), the transmission of a preamble signature or an AI is forbidden in all access slots.
When A equals to 1 (0001 in binary expression), the indices of the allowed access slots are 0 and 4 for any value of F.
When A equals to 2 (0010 in binary expression), the indices of the allowed access slots equal to 1 and 5 for any value of F. When A equals to 4 (0100) and 8 (1000), the indices of the allowed access slots are 2, 6 and 3, 7, respectively, for any value of F.
The indices for the other values of the parameter A are determined on the basis of the bit constellation in the binary expression of A, as in the case of TAICH = 0. Thus, all available slots are allowed in the case of A 15 (1111 in binary expression).
In general, the allowed downlink access slots are determined by (Fxd, axd)l =(Fxu, axu)l + 2, for A = x and TAICH = 1. Thus, basically, the indices of the downlink access slots are obtained by increasing the indices of the uplink access slots by 2.
Thus, the number of allowed PRACH uplink access slots and AICH downlink access slots can be configured in accordance with the requirements of the random access communication or the hardware resources at the BTS 10.
[Second example]
According to the second example of the preferred embodiment, fifteen access slots are provided per 20 ms, wherein two consecutive radio frames 2=F and 2=F+1 (0 s F s (NF/2-1)) contain fifteen PRACH or AICH access slots each having an index a, where 0 s a s 15. In the present case, the two consecutive radio frames 2=F and 2=F+1 are denoted by I' indicating a PRACH or an AICH frame of length 20 ms.
Thus, I' contains 15 access slots having a length of roughly 1.33 ms (20ms/15). The frame index I' ranges from 0 to (NF/2-1).
Fig. 5 shows a table indicating the relationship between the allowed access slots and the parameter A in case the value of TAICH = 0=
In case of TAICH = 0, i.e. 0 s A s 7, the transmission of a preamble signature or an AI is also forbidded in all access slots, if A equals to 0 (000 in binary expression).
When A equals to 1 (001 in binary expression), allowed access slots indices are 0, 3, 6, 9, and 12, i.e.
(rlu, 0) 0, (rlu, 3) 0, (rlu, 6) 0, (rlu, 9) 0, and (I'lu, 12) 0, for any I', since the cycle of the PRACH access slot timing is one radio frame.
When A equals to 2 (010 in binary expression), allowed access slots (I'2u, a2u)0 are obtained by (I,lu, alu)0 + 1 for all available access slots (I'lu, alu)0, i.e. allowed access slot indices are 1, 4, 7, 10, and 13. Now, (I'1, al) =(I', a) + 1 is defined by I'1 =(I' + al/15) modulo NF/2 and al = (a + 1) modulo 15. Thus, allowed access slots are (r2u, 1) 0, (r2u= 4) 0, (r2u, 7) 0, (I'2u, 10) 0, and (r2u, 13) 0, for any F.
Similarly, when A equals to 4 (100 in binary expression), allowed access slot indices are 2, 5, 8, 11, and 14, since (I'4u, a4u) 0=(I'2u, a2u) 0+ 1.
In general, downlink access slots are obtained from (rxd, axd) 0=(I'xu, axu) 0+ 1.
Fig. 6 shows a table indicating allowed subsets of access slots in dependence on the parameter A and the frame index I', in case the value of the parameter TAICH equals to 1.
In the case of TAICH = 1, i.e. 0 s A s 15, the transmission of a preamble signature of an AI is again forbidded in all access slots, as long as A equals to 0 (0000 in binary expression).
When A equals to 1 (0001 in binary expression), allowed access slots indices for any frame Fare obtained from the equation:
i = 4- N +(I' modulo 4) where 0 s N s 3, wherein N is an integer number and i denotes the index of the allowed access slot, wherein only access slots having indices within the range 0 to 14 are valid.
When A equals to 2, 4 or 8, allowed access slots are obtained from (I'2nu, a2nu) 1=(]Fnu, anu) 1+ 1. Thus access slot indices for the case A = 2 can be computed from the indices obtained for the case A = 1, etc.
In general, downlink access slots are obtained from (I'xd, axd) 1 = ( I ' x u , axu) 1+ 2.
It is to be noted that, also in the second example, the sets of allowed access slots are determined for the other values of the parameter A by combining (adding) the subsets shown in the tables of Figs. 5 and 6 in accordance with the bit values of the respective binary expressions of the remaining parameter values, as described in the first example.
In the following, the selection of one or a plurality of access slots by the slot selection unit 24 of the MS 20 is described in greater detail.
The slot selection unit 24 may be arranged to randomly select one of the allowed uplink access slots determined based on e.g. one of the algorithms described in the first or second examples by the slot determination unit 23. Once the selection is done, consecutive preambles may be transmitted either three or four access slots apart (preamble-to-preamble timing), depending on the value of TAICH. Therefore, the MS 20 randomly picks a number x defining the subset of access slots which will be used by the MS 20. For TAICH = 0 and TAICH = 1, the values of x may be taken from the sets {l, 2, 41 and {1, 2, 4, 8}, respectively. Then, the selected uplink access slots are defined by all (Fxu, axu)'s or (I'xu, axu)'s, respectively.
Alternatively, the slot selection unit 24 of the MS 20 may be arranged to randomly select any allowed uplink access slot, when a preamble signature needs to be transmitted.
Once the access slot has been selected, the PRACH and AICH
timings are followed. Therefore, each time a preamble signature needs to be transmitted, the slot selection unit 24 of the MS 20 randomly selects a number x from the sets 11, 2, 4} or {1, 2, 4, 8} (depending on the value of TAICH) and then transmits using the next allowed access slot of (Fxu, axu) or (I'xu, axu), respectively. In this case, the preamble-to-preamble timing may be three, four or five access slots, depending on the value of x (case TAICH = 0)=
For TAICH = 1, the preamble-to-preamble timing may be four, five, six or seven slots, depending on the value of x.
It is to be pointed out that the random access method and system described in the preferred embodiment can be applied to any radio network having a random access function between mobile terminals and fixed network elements.
Furthermore, the discrete hardware units of the MS 20 and BTS 10 may be replaced by corresponding software features of a control program controlling a CPU provided in the BTS
10 or the MS 20. The above description of the preferred embodiment and the accompanying drawings are only intended to illustrate the present invention. The preferred embodiment of the invention may vary within the scope of the attached claims.
In summary, the present invention relates to a method and system for performing a random access operation between a mobile station and a network element such as a base transceiver station, wherein allowed access slots for random access channels are defined by the network and signaled to the mobile station. The definition of the allowed access slots is performed on the basis of a parameter set by the base transceiver station and transmitted to the mobile station which determines the allowed access slots based on the parameter. Thus, the number of allowed access slots can be defined by the network and can be changed dynamically based on the random access messaging load and the hardware requirements.
According to a further broad aspect of the present invention there is provided a method for performing random access in a mobile communication network having a base transceiver station and a plurality of mobile stations. The method comprises the steps of transmitting a parameter defining allowed access slots of at least one physically existing random access channel to said mobile station;
determining said allowed access slots at said mobile station based on said parameter; and using at least one of said determined allowed access slots for performing a ran access operation to said base transceiver station.
According to a further broad aspect of the present invention there is provided a system for performing random access in a mobile communication network. The system comprises a network element arranged for transmitting a parameter defining allowed access slots of at least one physically existing random access channel; and a plurality of mobile stations arranged for receiving said transmitted parameter, for determining said allowed access slots based on said received parameter, and for using at least one of said determined allowed access slots for performing a random access operation to said base transceiver station.
According to a still further broad aspect of the present invention there is provided a network element for a mobile communication network comprising a plurality of mobile - 7a -stations. The network element comprises setting means for setting a parameter defining allowed access slots of at least one physically existing random access channel for performing a random access operation; and transmitting means for transmitting said parameter to said plurality of mobile stations.
According to a still further broad aspect of the present invention there is provided a mobile station for a mobile communication network having at least one network element allowing a random access operation. The mobile station comprises receiving means for receiving a parameter defining allowed access slots of at least one physically existing random access channel for said random access operation from said network element; determining means for determining said allowed access slots based on said received parameter; and transmitting means for transmitting a random access message to said network element using at least one of said determined allowed access slots.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the present invention will be described in greater detail on the basis of a preferred embodiment with reference to the accompanying drawings, in which:
Fig. 1 shows a random access timing used in a random access channel according to a first example of the preferred embodiment of the present invention;
Fig. 2 shows a principle block diagram of a base transceiver station and a mobile station according to the preferred embodiment of the present invention ;
- 7b -Fig. 3 shows a table indicating a relationship between allowed access slots, a radio frame index and received parameters, according to a first example of the preferred embodiment of the present invention;
Fig. 4 shows a table indicating a relationship between allowed access slots and received parameters according to the first example of the preferred embodiment of the present invention;
- $ -Fig. 5 shows a table indicating a relationship between allowed access slots and received parameters according to a second example of the preferred embodiment of the present invention; and Fig. 6 shows a table indicating a relationship between allowed access slots, a radio frame index and received parameters, according to the second example of the preferred embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, the preferred embodiment of the method and system according to the present invention will be described on the basis of a WCDMA system.
Before a mobile station (MS) can start transmitting on the PRACH channel, it needs to acquire several parameters by decoding a message broadcast from a base transceiver station (BTS) via the Broadcast Channel (BCH). In particular, the MS needs to know e.g. the available access slots of the PRACH and AICH channels and the AICH
transmission timing parameter TAICH= These parameters must also be known at a layer 1 transceiver of the BTS, so that a PRACH reception and a AICH transmission can be performed.
According to the preferred embodiment of the present invention, the MS or a BTS can derive the available access slots on the basis of a parameter A transmitted via the BCH. Thus, the allowed access slots are defined on the basis of the parameters A and TAICH. However, the present invention is not restricted thereto, i.e. the allowed access slots may as well be defined solely on the basis of the parameter A alone.
After the allowed access slots have been determined at the MS, the MS selects an access slot in which a preamble signature will be transmitted.
[First example]
Fig. 1 shows a first example of a possible timing configuration of the random access channels. In this case, a radio frame of the random access channels has a length of 10 ms, wherein both uplink and downlink access slots have a length of 1.25 ms, such that each radio frame comprises eight access slots which can be allowed for the random access operation. For each uplink access slot, a corresponding downlink access slot is provided. Preambles and AIs are transmitted in time alignment with the uplink and downlink access slots, respectively. An uplink access slot is transmitted a specified time period before the corresponding downlink access slot. This ti,,r~e period is equal to 1.75 ms or 3 ms for TAICH = 0 and TAICH = 1, respectively.
However, the present invention is not restricted to the above timing. Any other timing scheme, such as 15 access slots per 20 ms according to the second example described later, could be implemented as well.
The RACH message can be transmitted either three or four access slots after the latest transmitted preamble, depending on the value of TAZCx. The timing offset between uplink and downlink access slots, as seen from the MS, is equal to 0.5 ms. Therefore, an access slot starts 0.5 ms earlier in the uplink direction as compared to the downlink direction.
According to Fig. 1, the access slots in each frame F are denoted by indices 0 to 7, and the radio frames F are numbered from 0 to (NF-1), wherein NF denotes the number of available radio frames indices. In the above alternative case of e.g. 15 access slots per 20ms (not shown), the access slots are denoted by indices 0 to 14.
In general, NF must be an integer number large enough to enable a selection combining in a switching means such as a radio network controller (RNC). This can be achieved, if NF
satisfies the following conditions:
(NF - 1) modulo 3 = 2, and (NF/2 - 1) modulo 4 = 3 Fig. 2 shows a principle block diagram of a BTS 10 and an MS 20 according to the preferred embodiment of the present invention.
The BTS 10 comprises a transceiver (TRX) 11 for receiving and transmitting messages via corresponding radio channels to the MS 20. Furthermore, the BTS 10 comprises a parameter setting unit 14 in which random access parameters such as the parameter A and the timing parameter TAICH are set. The setting may be controlled by the BTS 10 or on the basis of an external command received from the mobile network.
The parameter setting unit 14 is connected to a random access (RAC) control unit 15 for performing a signal processing required for the random access operations via the BCH and AICH channels. Based on the parameters received from the parameter setting unit 14 the RAC control unit 15 supplies a corresponding broadcast message to the TRX 11 which transmits the broadcast message to MSs located in the corresponding radio cell controlled by the BTS 10.
Furthermore, the RAC control unit 15 is connected to a switch 13 by means of which a connection to another network element such as a radio network controller (RNC) can be established in order to receive e.g. a control command for externally controlling the parameter setting unit 14.
In case the BTS 10 receives a random access message from the MS 20 via the PRACH channel, the TRX 11 supplies the received message to a slot determination unit 12 arranged to detect an index of the uplink access slot selected by the MS 20 from the allowed access slots defined by the parameters A and TAICH. Based on the detected index of the received uplink access slot, the slot determination unit 12 determines indices of allowed downlink slots of the AICH
channel, to be used for transmitting a response message to the MS 20. The determination of the indices of the allowed downlink access slots is performed on the basis of an algorithm described later.
Additionally, the slot determination unit 12 is connected to the switch 13 in order to supply received random access messages to the network.
The MS 20 comprises a TRX 21 for transmitting and receiving messages via corresponding radio channels. The TRX 21 is connected to a parameter extraction unit 22, where the random access parameters such as the parameter A and the parameter TAICH are extracted from the BCH channel. The extracted parameters are supplied to a slot determination unit 23 arranged to determine the allowed uplink access slots based on a predefined algorithm which may depend on the value of the parameter TAICH and which is described later. The determined allowed access slots are supplied to a slot selection unit 24 in which at least one desired uplink access slot is selected. The uplink access slot may be selected randomly based on the determined allowed access slots. Once the selection is done, consecutive preambles are transmitted either three or four access slots apart, depending on the value of the parameter TAICH=
Alternatively, the MS 20 may randomly select a number which defines a subset of the determined allowed access slots, which the MS 20 will then use for transmitting the random access message.
The index of the selected access slot is supplied to a random access (RAC) control unit 25 arranged for performing a signal processing required for the random access operations via the PRACH channel. The RAC control unit 25 generates a random access message based on an information supplied from an I/0 unit 27 via a signal processing unit 26 to the TRX 21, in order to be transmitted via the PRACH
channel to the BTS 10. The signal processing unit 26 is provided for performing the required base band signaling of any input or output signal exchanged between the RAC
control unit 25 and the I/O unit 27.
In the following, algorithms used by the slot determining unit 23 and the RAC control unit 15 for determining allowed uplink and, respectively, downlink access slots based on the parameters A and TAICH are described with reference to Figures 3 and 4.
As already mentioned, each radio frame F may contain eight access slots each having a respective index a, wherein 0 s a s 7. The index of the radio frame F ranges between 0 and (NF-1). Alternatively, two consecutive radio frames 2=F and 2=F+l which form a 20 ms frame I' may contain fifteen access slots, i.e. 0 s a s 14.
Initially, the network, e.g. the BTS 10, informs the mobile stations, located within the covered radio area, of the available access slots of the PRACH and AICH channel by transmitting the parameters TAICH and A in the BCH channel, wherein TAICH may be equal to 0 or 1. In case TAICH = 0, the value of A may range between 0 and 7 (i.e. 0 s A s 7, or 000 s A s 111 in binary expression). In case the value of TAICH equals to 1, the values of the parameter A may range between 0 and 15 (i.e. 0 s A s 15, or 0000 s A s 1111 in binary expression).
According to the preferred embodiment, each bit of the binary expression of the parameter A indicates either an inclusion or an exclusion of a subset of access slots to the set of allowed access slots.
Fig. 3 shows a table indicating allowed subsets of access slots in dependence on the parameter A and the frame index F, in case the value of the parameter TAICH equals to 0.
In case A is equal to 0 (000 in binary expression), the transmission of a preamble signature or an AI is forbidden or disabled in all access slots, since each bit of the binary expression is 0.
When A equals to 1 (001 in binary expression), the indices of the allowed uplink access slots in any radio frame F are obtained by the equation:
i = 3- N + (F modulo 3) where 0 s N s 2, wherein N is an integer number and i denotes the index of the allowed access slot, wherein only access slots having indices within the range 0 to 7 are valid. Based on the above equation, the values indicated in the column A = 1 of the table shown in Fig. 3 are obtained.
Since each bit of the parameter A indicates either an inclusion or exclusion of a subset of access slots, the subsets are defined by A = 1 (001), A = 2 (010) and A = 4 (100), which reflect the binary weights of the binary expression.
Basically, the subsets for A = 2 are obtained by increasing the indices of the subsets for A = 1 by one, wherein the value 8 is deleted and transferred as a value 0 to the next radio frame F+1. Similarly, the subset of allowed access slots for A = 4 is obtained from the subset for A = 2 by increasing the indices by one and transferring an obtained value 8 as a value 0 to the subsequent radio frame. Thus, an offset added to a basic subset (A = 1) is determined by the value of the parameter A.
The other sets of allowed access slots for the remaining values of the parameter A can be determined by adding respective ones of the subsets given in the table of Fig. 3 based on the bit values in the binary expression of the parameter A. E.g., in case the parameter A equals to 7 having the binary expression 111 and thus including all binary weights, the subsets for A = 1, A = 2 and A = 4 are all included in the set of allowed access slots, which leads to the maximum allowable slot number. Furthermore, in case A equals to 5 having the binary expression 101, the subsets defined by A = 1 and A = 4 are added to obtain the set of allowed access slots, and so on.
In the following, an index of an access slot is denoted by a pair (F, a), wherein F (0 s F s(NF-1)) denotes the frame index and a (0 s a s 7) denotes the access slot index (within a frame F). E.g., the allowed access slots for A
1 and F = 0, shown in Fig. 3, can be expressed as (0,0) (0,3) and (0, 6) .
(Flu, alu)0 denotes any uplink access slot for A = 1 and TAICH = 0. The corresponding downlink access slots determined by the slot determination unit 12 of the BTS 10 are given by (Fld, ald)0, wherein Fld =(Flu + ald/8) modulo NF and ald =(alu + 1) modulo 8 in the above case of eight access slots per radio frame. In the equation for Fld õ/" stands for an integer division, i.e. truncation. Thus, in general, a downlink access slot is given by (Fxd, axd)0 =(Fxuaxu)0 + 1, for A = x and TAICH = 0-Accordingly, when A equals to 2 (010 in binary expression), the allowed uplink access slots are defined by (F2u, a2u) 0 =(Flu, alu) 0 + 1. Similarly, (F4u, a4u)0 =
(F2u, a2u)0 + 1.
Due to the modulo 3 operation for the frame index F, the allowed access slots are changed over three consecutive radio frames. The reason therefore is that the cycle of the PRACH access slot timing is 30 ms, which corresponds to three radio frames.
Fig. 4 shows a table indicating the relationship between the allowed access slots and the parameter A in case the value of TAICH = 1=
In this case, the allowed access slots are equal in any radio frame, i.e. the determination is performed irrespective of the frame index F. This is due to the fact that the cycle of the PRACH access slot timing is one radio frame if TAICH = 1=
When TAICH = 1, the parameter A ranges between 0 and 15, i.e. comprises four bits in the binary expression.
Therefore, four different sets of allowed access slots are defined, wherein each bit of the parameter A indicates either an inclusion or exclusion of the corresponding set of allowed access slots.
When A equals to 0 (0000 in binary expression), the transmission of a preamble signature or an AI is forbidden in all access slots.
When A equals to 1 (0001 in binary expression), the indices of the allowed access slots are 0 and 4 for any value of F.
When A equals to 2 (0010 in binary expression), the indices of the allowed access slots equal to 1 and 5 for any value of F. When A equals to 4 (0100) and 8 (1000), the indices of the allowed access slots are 2, 6 and 3, 7, respectively, for any value of F.
The indices for the other values of the parameter A are determined on the basis of the bit constellation in the binary expression of A, as in the case of TAICH = 0. Thus, all available slots are allowed in the case of A 15 (1111 in binary expression).
In general, the allowed downlink access slots are determined by (Fxd, axd)l =(Fxu, axu)l + 2, for A = x and TAICH = 1. Thus, basically, the indices of the downlink access slots are obtained by increasing the indices of the uplink access slots by 2.
Thus, the number of allowed PRACH uplink access slots and AICH downlink access slots can be configured in accordance with the requirements of the random access communication or the hardware resources at the BTS 10.
[Second example]
According to the second example of the preferred embodiment, fifteen access slots are provided per 20 ms, wherein two consecutive radio frames 2=F and 2=F+1 (0 s F s (NF/2-1)) contain fifteen PRACH or AICH access slots each having an index a, where 0 s a s 15. In the present case, the two consecutive radio frames 2=F and 2=F+1 are denoted by I' indicating a PRACH or an AICH frame of length 20 ms.
Thus, I' contains 15 access slots having a length of roughly 1.33 ms (20ms/15). The frame index I' ranges from 0 to (NF/2-1).
Fig. 5 shows a table indicating the relationship between the allowed access slots and the parameter A in case the value of TAICH = 0=
In case of TAICH = 0, i.e. 0 s A s 7, the transmission of a preamble signature or an AI is also forbidded in all access slots, if A equals to 0 (000 in binary expression).
When A equals to 1 (001 in binary expression), allowed access slots indices are 0, 3, 6, 9, and 12, i.e.
(rlu, 0) 0, (rlu, 3) 0, (rlu, 6) 0, (rlu, 9) 0, and (I'lu, 12) 0, for any I', since the cycle of the PRACH access slot timing is one radio frame.
When A equals to 2 (010 in binary expression), allowed access slots (I'2u, a2u)0 are obtained by (I,lu, alu)0 + 1 for all available access slots (I'lu, alu)0, i.e. allowed access slot indices are 1, 4, 7, 10, and 13. Now, (I'1, al) =(I', a) + 1 is defined by I'1 =(I' + al/15) modulo NF/2 and al = (a + 1) modulo 15. Thus, allowed access slots are (r2u, 1) 0, (r2u= 4) 0, (r2u, 7) 0, (I'2u, 10) 0, and (r2u, 13) 0, for any F.
Similarly, when A equals to 4 (100 in binary expression), allowed access slot indices are 2, 5, 8, 11, and 14, since (I'4u, a4u) 0=(I'2u, a2u) 0+ 1.
In general, downlink access slots are obtained from (rxd, axd) 0=(I'xu, axu) 0+ 1.
Fig. 6 shows a table indicating allowed subsets of access slots in dependence on the parameter A and the frame index I', in case the value of the parameter TAICH equals to 1.
In the case of TAICH = 1, i.e. 0 s A s 15, the transmission of a preamble signature of an AI is again forbidded in all access slots, as long as A equals to 0 (0000 in binary expression).
When A equals to 1 (0001 in binary expression), allowed access slots indices for any frame Fare obtained from the equation:
i = 4- N +(I' modulo 4) where 0 s N s 3, wherein N is an integer number and i denotes the index of the allowed access slot, wherein only access slots having indices within the range 0 to 14 are valid.
When A equals to 2, 4 or 8, allowed access slots are obtained from (I'2nu, a2nu) 1=(]Fnu, anu) 1+ 1. Thus access slot indices for the case A = 2 can be computed from the indices obtained for the case A = 1, etc.
In general, downlink access slots are obtained from (I'xd, axd) 1 = ( I ' x u , axu) 1+ 2.
It is to be noted that, also in the second example, the sets of allowed access slots are determined for the other values of the parameter A by combining (adding) the subsets shown in the tables of Figs. 5 and 6 in accordance with the bit values of the respective binary expressions of the remaining parameter values, as described in the first example.
In the following, the selection of one or a plurality of access slots by the slot selection unit 24 of the MS 20 is described in greater detail.
The slot selection unit 24 may be arranged to randomly select one of the allowed uplink access slots determined based on e.g. one of the algorithms described in the first or second examples by the slot determination unit 23. Once the selection is done, consecutive preambles may be transmitted either three or four access slots apart (preamble-to-preamble timing), depending on the value of TAICH. Therefore, the MS 20 randomly picks a number x defining the subset of access slots which will be used by the MS 20. For TAICH = 0 and TAICH = 1, the values of x may be taken from the sets {l, 2, 41 and {1, 2, 4, 8}, respectively. Then, the selected uplink access slots are defined by all (Fxu, axu)'s or (I'xu, axu)'s, respectively.
Alternatively, the slot selection unit 24 of the MS 20 may be arranged to randomly select any allowed uplink access slot, when a preamble signature needs to be transmitted.
Once the access slot has been selected, the PRACH and AICH
timings are followed. Therefore, each time a preamble signature needs to be transmitted, the slot selection unit 24 of the MS 20 randomly selects a number x from the sets 11, 2, 4} or {1, 2, 4, 8} (depending on the value of TAICH) and then transmits using the next allowed access slot of (Fxu, axu) or (I'xu, axu), respectively. In this case, the preamble-to-preamble timing may be three, four or five access slots, depending on the value of x (case TAICH = 0)=
For TAICH = 1, the preamble-to-preamble timing may be four, five, six or seven slots, depending on the value of x.
It is to be pointed out that the random access method and system described in the preferred embodiment can be applied to any radio network having a random access function between mobile terminals and fixed network elements.
Furthermore, the discrete hardware units of the MS 20 and BTS 10 may be replaced by corresponding software features of a control program controlling a CPU provided in the BTS
10 or the MS 20. The above description of the preferred embodiment and the accompanying drawings are only intended to illustrate the present invention. The preferred embodiment of the invention may vary within the scope of the attached claims.
In summary, the present invention relates to a method and system for performing a random access operation between a mobile station and a network element such as a base transceiver station, wherein allowed access slots for random access channels are defined by the network and signaled to the mobile station. The definition of the allowed access slots is performed on the basis of a parameter set by the base transceiver station and transmitted to the mobile station which determines the allowed access slots based on the parameter. Thus, the number of allowed access slots can be defined by the network and can be changed dynamically based on the random access messaging load and the hardware requirements.
Claims (33)
1. A method for performing random access in a mobile communication network having a base transceiver station and a plurality of mobile stations, comprising:
a) transmitting a parameter defining allowed access slots of at least one physically existing random access channel to said mobile station;
b) determining said allowed access slots at said mobile station based on said parameter; and c) using at least one of said determined allowed access slots for performing a ran access operation to said base transceiver station.
a) transmitting a parameter defining allowed access slots of at least one physically existing random access channel to said mobile station;
b) determining said allowed access slots at said mobile station based on said parameter; and c) using at least one of said determined allowed access slots for performing a ran access operation to said base transceiver station.
2. A method according to claim 1, wherein said parameter is transmitted via a broadcast channel.
3. A method according to claim 2, wherein said broadcast channel is the BCH channel of a WCDMA system.
4. A method according to claim 2 or 3, wherein said random access is performed via the PRACH uplink channel and the AICH
downlink channel of the WCDMA system.
downlink channel of the WCDMA system.
5. A method according to any one of claims 1 to 4, wherein said parameter defines a subset of available access slots of said mobile communication network.
6. A method according to claim 5, wherein said subset is determined by another parameter transmitted from said base transceiver station to said mobile station.
7. A method according to claim 6, wherein said other parameter is a timing parameter defining a transmission timing of an uplink access slot.
8. A method according to claim 6 or 7, wherein said other parameter is transmitted via a broadcast channel.
9. A method according to any one of claims 6 to 8, wherein the bit number of said parameter is changed in dependence on said other parameter.
10. A method according to any one of claims 1 to 9, wherein a transmission of a preamble signature or an acquisition indication is disabled in dependence of the value of said parameter.
11. A method according to any one of claims 1 to 10, wherein an index of an allowed uplink access slot is calculated on the basis of the value of said parameter and a frame number of a frame used for transmitting an uplink access slot.
12. A method according to claim 11, wherein said index is calculated by using the equation i = 3.cndot.N + (F modulo 3) where 0 <= N <= 2, wherein F and N are integer numbers, and F denotes said frame number, and wherein only access slots having indices within the range 0 to 7 are valid.
13. A method according to claim 11, wherein said index is calculated by using the equation i = 4 .cndot. N + (.GAMMA. modulo 4) where 0 <= N <= 3, wherein .GAMMA. and N are integer numbers, and .GAMMA. denotes a frame number indicating two consecutive ones of said frame numbers of said frame used for transmitting an uplink access slot, and wherein only access slots having indices within the range 0 to 14 are valid.
14. A method according to claim 12 or 13, wherein said parameter determines an offset to be added to said calculated index.
15. A method according to any one of claims 1 to 11, wherein an index of an allowed uplink access slot is determined on the basis of the value of said parameter irrespective of a frame number of a frame used for transmitting an uplink access slot.
16. A method according to any one of claims 1 to 15, wherein an allowed downlink slot is determined by adding a predetermined value to an index of a received uplink slot.
17. A method according to claim 16, wherein said predetermined value is selected in accordance with a timing parameter defining a transmission timing of said uplink slot.
18. A method according to any one of claims 1 to 17, wherein bit values of a binary expression of said parameter determines a combination of calculated indices obtained for other values of said parameter, said other values corresponding to the binary weights of said binary expression.
19. A system for performing random access in a mobile communication network, comprising:
a) a network element (10) arranged for transmitting a parameter defining allowed access slots of at least one physically existing random access channel; and b) a plurality of mobile stations (20) arranged for receiving said transmitted parameter, for determining said allowed access slots based on said received parameter, and for using at least one of said determined allowed access slots for performing a random access operation to said base transceiver station (10).
a) a network element (10) arranged for transmitting a parameter defining allowed access slots of at least one physically existing random access channel; and b) a plurality of mobile stations (20) arranged for receiving said transmitted parameter, for determining said allowed access slots based on said received parameter, and for using at least one of said determined allowed access slots for performing a random access operation to said base transceiver station (10).
20. A system according to claim 19, wherein said network element is a WCDMA base transceiver station (10) and said mobile station (20) is a WCDMA mobile station.
21. A network element for a mobile communication network comprising a plurality of mobile stations (20), comprising:
a) setting means (14) for setting a parameter defining allowed access slots of at least one physically existing random access channel for performing a random access operation; and b) transmitting means (11) for transmitting said parameter to said plurality of mobile stations (20).
a) setting means (14) for setting a parameter defining allowed access slots of at least one physically existing random access channel for performing a random access operation; and b) transmitting means (11) for transmitting said parameter to said plurality of mobile stations (20).
22. A network element according to claim 21, wherein said network element is a WCDMA base transceiver station (10).
23. A network element according to claim 21 or 22, wherein said transmitting means (11) is arranged to transmit said parameter via a broadcast channel.
24. A network element according to anyone of claims 21 to 23, wherein said setting means (14) is arranged to set said parameter in dependence on a timing parameter value defining a transmission timing of an uplink access slot in said random access operation.
25. A mobile station for a mobile communication network having at least one network element (10) allowing a random access operation, comprising;
a) receiving means (21) for receiving a parameter defining allowed access slots of at least one physically existing random access channel for said random access operation from said network element (10);
b) determining means (23) for determining said allowed access slots based on said received parameter; and c) transmitting means (21) for transmitting a random access message to said network element (10) using at least one of said determined allowed access slots.
a) receiving means (21) for receiving a parameter defining allowed access slots of at least one physically existing random access channel for said random access operation from said network element (10);
b) determining means (23) for determining said allowed access slots based on said received parameter; and c) transmitting means (21) for transmitting a random access message to said network element (10) using at least one of said determined allowed access slots.
26. A mobile station according to claim 25, wherein said receiving means (21) is arranged to receive said parameter via a broadcast channel.
27. A mobile station according to claim 26, wherein said determining means (23) is arranged to determine said allowed access slots on the basis of said received parameter and a timing parameter received via said broadcast channel.
28. A mobile station according to anyone of claims 25 to 27, wherein said determining means (23) is arranged to calculate an index of an allowed uplink access slot on the basis of the value of said received parameter and a frame number of a frame used for transmitting an uplink access slot.
29. A mobile station according to anyone of claims 25 to 27, wherein said determining means (23) is arranged to determine an index of an allowed uplink access slot on the basis of the value of said parameter irrespective of a frame number of a frame used for transmitting an uplink access slot.
30. A mobile station according to anyone of claims 25 to 29, wherein a selection means (24) is provided for randomly selecting from allowed access slots determined by said determining means (23) an uplink access slot to be used for transmitting a preamble of said random access message.
31. A mobile station according to claim 30, wherein consecutive preambles are transmitted a predetermined number of access slots apart.
32. A mobile station according to claim 31, wherein said predetermined number depends on a timing parameter received by said receiving means (21).
33. A mobile station according to claim 30, wherein said selection means (24) is arranged to perform said random selection any time a preamble needs to be transmitted.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EP1999/003630 WO2000074416A1 (en) | 1999-05-26 | 1999-05-26 | Random access control method and system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2374854A1 CA2374854A1 (en) | 2000-12-07 |
| CA2374854C true CA2374854C (en) | 2008-02-05 |
Family
ID=8167306
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002374854A Expired - Lifetime CA2374854C (en) | 1999-05-26 | 1999-05-26 | Random access control method and system |
Country Status (11)
| Country | Link |
|---|---|
| US (1) | US9282573B2 (en) |
| EP (1) | EP1188344B1 (en) |
| JP (1) | JP3928777B2 (en) |
| KR (1) | KR20020008196A (en) |
| CN (1) | CN1199506C (en) |
| AU (1) | AU4500999A (en) |
| BR (1) | BR9917317B1 (en) |
| CA (1) | CA2374854C (en) |
| DE (1) | DE69914108T2 (en) |
| ES (1) | ES2211101T3 (en) |
| WO (1) | WO2000074416A1 (en) |
Families Citing this family (58)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69940933D1 (en) * | 1998-10-05 | 2009-07-09 | Sony Deutschland Gmbh | Direct access burst transmission with at least one message part |
| CA2374854C (en) * | 1999-05-26 | 2008-02-05 | Nokia Networks Oy | Random access control method and system |
| CN1172463C (en) * | 2000-06-12 | 2004-10-20 | 三星电子株式会社 | Method of assigning uplink random access channel in CDMA mobile communication system |
| FR2838277A1 (en) * | 2002-04-05 | 2003-10-10 | Mitsubishi Electric Telecom Eu | METHOD FOR RANDOM ACCESS TO A PHYSICAL CHANNEL WITH RANDOM ACCESS AND MOBILE STATION USING THE SAME |
| TWI259000B (en) | 2002-08-07 | 2006-07-21 | Interdigital Tech Corp | Channel switching for support of multimedia broadcast and multicast services |
| TWI324896B (en) * | 2002-09-26 | 2010-05-11 | Interdigital Tech Corp | Method for providing fast feedback information for random access channel in a wireless communication system |
| US7706824B2 (en) * | 2002-09-27 | 2010-04-27 | Telefonaktiebolaget L M Ericsson (Publ) | Requesting and controlling access in a wireless communications network |
| GB2398455B (en) * | 2003-02-11 | 2007-09-26 | Ipwireless Inc | Method, base station and mobile station for TDD operation in a communication system |
| EP1478131A1 (en) * | 2003-05-12 | 2004-11-17 | Siemens Aktiengesellschaft | Method for random access in a lokal network |
| EP2429099A3 (en) * | 2003-05-28 | 2014-04-30 | Nvidia Corporation | Method, base station and mobile station for tdd operation in a communication system |
| KR100605800B1 (en) * | 2003-11-12 | 2006-07-31 | 삼성전자주식회사 | Mobile terminal for implementing quality of service at random access stage and method thereof |
| JP4054878B2 (en) * | 2004-03-08 | 2008-03-05 | 独立行政法人情報通信研究機構 | COMMUNICATION SYSTEM, COMMUNICATION METHOD, AND BASE STATION |
| GB0408383D0 (en) * | 2004-04-15 | 2004-05-19 | Koninkl Philips Electronics Nv | A radio network and a method of operating a radio network |
| CN100418386C (en) * | 2005-08-26 | 2008-09-10 | 清华大学 | Dynamic channel switching-in method based on useable channel searching |
| JP4667194B2 (en) | 2005-10-07 | 2011-04-06 | 株式会社エヌ・ティ・ティ・ドコモ | Regulation control system, radio communication terminal apparatus, regulation control method, radio communication terminal control method |
| RU2433574C2 (en) * | 2005-10-21 | 2011-11-10 | Телефонактиеболагет Лм Эрикссон (Пабл) | Technique for performing random access procedure over radio interface |
| BRPI0617783A2 (en) | 2005-10-31 | 2011-08-09 | Lg Electronics Inc | method of transmitting and receiving radio access information in a wireless mobile communications system |
| KR20070047124A (en) | 2005-11-01 | 2007-05-04 | 엘지전자 주식회사 | Method for transmitting and receiving wireless resource information |
| WO2007052971A1 (en) * | 2005-11-04 | 2007-05-10 | Lg Electronics Inc. | Random access dimensioning methods and procedures for frequency division multiplexing access systems |
| TWI378690B (en) | 2005-11-28 | 2012-12-01 | Lg Electronics Inc | Method and apparatus for generatin and transmitting code sequence in a wireless communication system |
| CN101064922B (en) * | 2006-04-30 | 2011-12-07 | 华为技术有限公司 | Method and system for preventing access interference in wireless communication |
| TWI625954B (en) | 2006-06-09 | 2018-06-01 | 進化無線責任有限公司 | Method and apparatus of transmitting data in a mobile communication system |
| US8064401B2 (en) | 2006-07-14 | 2011-11-22 | Qualcomm Incorporated | Expedited handoff |
| KR101387500B1 (en) | 2006-08-22 | 2014-04-21 | 엘지전자 주식회사 | Method of transmitting and receiving control information in wireless communicaiton system |
| KR20090053946A (en) * | 2006-09-15 | 2009-05-28 | 인터디지탈 테크날러지 코포레이션 | Method and apparatus for dynamic updates of random access parameters |
| KR100788901B1 (en) * | 2006-09-29 | 2007-12-27 | 한국전자통신연구원 | Method for operating random access channel in mobile communication system |
| KR100938754B1 (en) | 2006-10-30 | 2010-01-26 | 엘지전자 주식회사 | Data transmission method and data receiving method using discontinuous reception |
| US8428013B2 (en) * | 2006-10-30 | 2013-04-23 | Lg Electronics Inc. | Method of performing random access in a wireless communcation system |
| KR101233181B1 (en) * | 2006-10-30 | 2013-02-15 | 엘지전자 주식회사 | Random access method in wireless communication system |
| WO2008054114A2 (en) * | 2006-10-30 | 2008-05-08 | Lg Electronics Inc. | Methods for re-direction of uplink access and for controlling random access in mobile communication system |
| KR100884380B1 (en) * | 2006-12-08 | 2009-02-17 | 한국전자통신연구원 | Method for performing random access based on priority |
| US9113325B2 (en) * | 2007-04-25 | 2015-08-18 | Texas Instruments Incorporated | Signaling of random access preamble time-frequency location in wireless networks |
| US8081662B2 (en) | 2007-04-30 | 2011-12-20 | Lg Electronics Inc. | Methods of transmitting data blocks in wireless communication system |
| WO2008133485A1 (en) | 2007-04-30 | 2008-11-06 | Lg Electronics Inc. | Methods of generating data block in mobile communication system |
| US8027363B2 (en) | 2007-04-30 | 2011-09-27 | Lg Electronics Inc. | Method of transmitting data in a wireless communication system |
| KR100917205B1 (en) | 2007-05-02 | 2009-09-15 | 엘지전자 주식회사 | Method of configuring a data block in wireless communication system |
| EP2153597B1 (en) | 2007-05-03 | 2013-04-03 | LG Electronics Inc. | Method of data processing in a wireless communication system |
| HUE033683T2 (en) | 2007-06-18 | 2017-12-28 | Lg Electronics Inc | Method and user equipment for performing uplink synchronization in wireless communication system |
| KR101470638B1 (en) | 2007-06-18 | 2014-12-08 | 엘지전자 주식회사 | Method for enhancing radio resource and informing status report in mobile telecommunications system and receiver of mobile telecommunications |
| KR101476194B1 (en) | 2007-06-18 | 2014-12-24 | 엘지전자 주식회사 | Control channel reception method for receiving a broadcast or multicast service |
| WO2009038312A2 (en) | 2007-09-20 | 2009-03-26 | Lg Electronics Inc. | A method for handling correctly received but header compression failed packets |
| US9113477B2 (en) | 2007-09-27 | 2015-08-18 | Interdigital Patent Holdings, Inc. | Method and apparatus to allocate radio resources for transmitting a message part in an enhanced RACH |
| EP2574132A1 (en) * | 2007-12-12 | 2013-03-27 | Telefonaktiebolaget L M Ericsson (publ) | Extended random access configuration transmitted by a base station of an E-UTRAN for random access to a radio channel by a user equipment |
| TWI469668B (en) | 2007-12-31 | 2015-01-11 | Interdigital Patent Holdings | Method and apparatus for radio link synchronization and power control in cell_fach state |
| CN102625467B (en) * | 2008-01-07 | 2015-12-09 | 三星电子株式会社 | The equipment of transmitting random access preamble signal and method |
| CN101227723B (en) * | 2008-01-21 | 2011-03-16 | 中兴通讯股份有限公司 | Method for implementing subscriber terminal access control |
| US8428077B2 (en) * | 2008-03-31 | 2013-04-23 | Qualcomm Incorporated | Methods and apparatus for dynamic load balancing with E-AICH |
| CN102138360B (en) * | 2008-07-01 | 2014-06-11 | 爱立信电话股份有限公司 | Methods and apparatuses for performing preamble assignment for random access in a telecommunications system |
| US9480084B2 (en) | 2008-07-01 | 2016-10-25 | Telefonaktiebolaget Lm Ericsson (Publ) | Methods and apparatuses for performing preamble assignment for random access in a telecommunications system |
| US20100034141A1 (en) * | 2008-08-06 | 2010-02-11 | Qualcomm Incorporated | Method and apparatus for initiating random access procedure in wireless networks |
| KR100939722B1 (en) | 2008-08-11 | 2010-02-01 | 엘지전자 주식회사 | Data transmission method and user equipment for the same |
| CN101686544A (en) * | 2008-09-22 | 2010-03-31 | 中兴通讯股份有限公司 | Method for distributing special random access resource and base station |
| US8902826B2 (en) * | 2008-09-29 | 2014-12-02 | Qualcomm Incorporated | Physical random access channel resource selection |
| CN101753181B (en) * | 2008-12-12 | 2015-04-29 | 电信科学技术研究院 | Data transmission method, system and device |
| KR101607336B1 (en) * | 2009-06-07 | 2016-03-30 | 엘지전자 주식회사 | Apparatus and method of setting up radio bearer in wireless communication system |
| CN102264149B (en) * | 2010-05-26 | 2014-08-13 | 中兴通讯股份有限公司 | WCDMA system terminal random access method and apparatus thereof |
| CN107205281B (en) * | 2016-03-18 | 2020-11-10 | 中兴通讯股份有限公司 | Method for sending random access signal, method and device for notifying resource |
| US10548168B2 (en) * | 2016-12-01 | 2020-01-28 | Electronics And Telecommunications Research Institute | Method for random access in wireless communication system and apparatus for the same |
Family Cites Families (36)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5012469A (en) * | 1988-07-29 | 1991-04-30 | Karamvir Sardana | Adaptive hybrid multiple access protocols |
| US5172375A (en) * | 1989-06-22 | 1992-12-15 | Nec Corporation | Multiple access satellite communication system for mini-earth station networks |
| US5365516A (en) * | 1991-08-16 | 1994-11-15 | Pinpoint Communications, Inc. | Communication system and method for determining the location of a transponder unit |
| GB2281470B (en) * | 1993-04-02 | 1998-07-15 | Motorola Ltd | Multichannel random access communications system |
| JP3351792B2 (en) * | 1993-11-01 | 2002-12-03 | テレフオンアクチーボラゲツト エル エム エリクソン | Automatic resend request |
| US5822359A (en) * | 1994-10-17 | 1998-10-13 | Motorola, Inc. | Coherent random access channel in a spread-spectrum communication system and method |
| JP3231575B2 (en) * | 1995-04-18 | 2001-11-26 | 三菱電機株式会社 | Wireless data transmission equipment |
| US5673259A (en) * | 1995-05-17 | 1997-09-30 | Qualcomm Incorporated | Random access communications channel for data services |
| US5541924A (en) * | 1995-07-28 | 1996-07-30 | Motorola, Inc. | Method and device for channel contention and data transmission for packet-switched subscriber units in a communication system |
| US5752193A (en) * | 1995-09-01 | 1998-05-12 | Motorola, Inc. | Method and apparatus for communicating in a wireless communication system |
| US6314081B1 (en) * | 1996-01-18 | 2001-11-06 | Ericsson Inc. | High power short message service using dedicated carrier frequency |
| FI103467B (en) * | 1996-07-25 | 1999-06-30 | Nokia Telecommunications Oy | Cell expansion in a time-division cellular system |
| GB2317786B (en) * | 1996-09-25 | 2001-05-30 | Motorola Ltd | Communication system with a deamformed control channel and method of system control |
| FI104610B (en) * | 1997-03-27 | 2000-02-29 | Nokia Networks Oy | Allocation of a control channel in a packet radio network |
| US6075779A (en) * | 1997-06-09 | 2000-06-13 | Lucent Technologies, Inc. | Random access channel congestion control for broadcast teleservice acknowledgment messages |
| KR100446515B1 (en) * | 1997-09-13 | 2004-11-12 | 삼성전자주식회사 | Connection method of a wireless communication system, specially correlated to reducing time for a connection and a likelihood of a connection channel collision |
| US6073018A (en) * | 1997-12-11 | 2000-06-06 | Ericsson Inc | System and method for interworking of wireless communication systems with ISDN networks |
| US6643275B1 (en) * | 1998-05-15 | 2003-11-04 | Telefonaktiebolaget Lm Ericsson (Publ) | Random access in a mobile telecommunications system |
| US6674765B1 (en) * | 1998-05-22 | 2004-01-06 | Lucent Technologies Inc. | Methods and apparatus for random chip delay access priority in a communications system |
| US6393047B1 (en) * | 1998-06-16 | 2002-05-21 | Telefonaktiebolaget Lm Ericsson (Publ) | Quadriphase spreading codes in code division multiple access communications |
| US6606313B1 (en) * | 1998-10-05 | 2003-08-12 | Telefonaktiebolaget Lm Ericsson (Publ) | Random access in a mobile telecommunications system |
| EP2088830B1 (en) * | 1998-10-05 | 2015-04-08 | Sony Deutschland GmbH | Random access channel prioritization scheme |
| DE69940933D1 (en) * | 1998-10-05 | 2009-07-09 | Sony Deutschland Gmbh | Direct access burst transmission with at least one message part |
| DE69834639T2 (en) * | 1998-10-05 | 2006-12-14 | Sony Deutschland Gmbh | Automatic determination of the point for random access channel splitting method |
| US6724813B1 (en) * | 1998-10-14 | 2004-04-20 | Telefonaktiebolaget Lm Ericsson (Publ) | Implicit resource allocation in a communication system |
| US6836469B1 (en) * | 1999-01-15 | 2004-12-28 | Industrial Technology Research Institute | Medium access control protocol for a multi-channel communication system |
| US6438375B1 (en) * | 1999-03-04 | 2002-08-20 | Telefonaktiebolaget Lm Ericsson (Publ) | Coordinating different types of messages sent to mobile radios in a mobile communications system |
| US6567482B1 (en) * | 1999-03-05 | 2003-05-20 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and apparatus for efficient synchronization in spread spectrum communications |
| US6169759B1 (en) * | 1999-03-22 | 2001-01-02 | Golden Bridge Technology | Common packet channel |
| US6285662B1 (en) * | 1999-05-14 | 2001-09-04 | Nokia Mobile Phones Limited | Apparatus, and associated method for selecting a size of a contention window for a packet of data system |
| CA2374854C (en) * | 1999-05-26 | 2008-02-05 | Nokia Networks Oy | Random access control method and system |
| CN1244988C (en) * | 1999-07-07 | 2006-03-08 | 三星电子株式会社 | Channel assignment apparatus and method for vacuum packet channel in CDMA mobile communication system |
| US6937641B2 (en) * | 2001-02-28 | 2005-08-30 | Golden Bridge Technology, Inc. | Power-controlled random access |
| US7706824B2 (en) * | 2002-09-27 | 2010-04-27 | Telefonaktiebolaget L M Ericsson (Publ) | Requesting and controlling access in a wireless communications network |
| US7286484B2 (en) * | 2003-01-10 | 2007-10-23 | Chunghwa Telecom Co., Ltd. | Q-learning-based multi-rate transmission control (MRTC) scheme for RRC in WCDMA systems |
| DE10359268B4 (en) * | 2003-12-17 | 2011-05-19 | Infineon Technologies Ag | Device for generating transmission signals in a mobile radio station by means of a scrambling code generator for preambles and for transmission signals of dedicated physical channels |
-
1999
- 1999-05-26 CA CA002374854A patent/CA2374854C/en not_active Expired - Lifetime
- 1999-05-26 EP EP99927762A patent/EP1188344B1/en not_active Expired - Lifetime
- 1999-05-26 AU AU45009/99A patent/AU4500999A/en not_active Abandoned
- 1999-05-26 DE DE1999614108 patent/DE69914108T2/en not_active Expired - Lifetime
- 1999-05-26 BR BRPI9917317-4B1A patent/BR9917317B1/en not_active IP Right Cessation
- 1999-05-26 JP JP2001500586A patent/JP3928777B2/en not_active Expired - Lifetime
- 1999-05-26 KR KR1020017014947A patent/KR20020008196A/en not_active Application Discontinuation
- 1999-05-26 WO PCT/EP1999/003630 patent/WO2000074416A1/en not_active Application Discontinuation
- 1999-05-26 ES ES99927762T patent/ES2211101T3/en not_active Expired - Lifetime
- 1999-05-26 CN CNB998166561A patent/CN1199506C/en not_active Expired - Lifetime
-
2001
- 2001-11-06 US US10/014,153 patent/US9282573B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1199506C (en) | 2005-04-27 |
| CA2374854A1 (en) | 2000-12-07 |
| BR9917317B1 (en) | 2013-09-17 |
| CN1357212A (en) | 2002-07-03 |
| JP3928777B2 (en) | 2007-06-13 |
| EP1188344B1 (en) | 2004-01-07 |
| DE69914108D1 (en) | 2004-02-12 |
| KR20020008196A (en) | 2002-01-29 |
| BR9917317A (en) | 2006-01-31 |
| AU4500999A (en) | 2000-12-18 |
| DE69914108T2 (en) | 2004-11-18 |
| EP1188344A1 (en) | 2002-03-20 |
| US9282573B2 (en) | 2016-03-08 |
| US20020089957A1 (en) | 2002-07-11 |
| WO2000074416A1 (en) | 2000-12-07 |
| ES2211101T3 (en) | 2004-07-01 |
| JP2003501909A (en) | 2003-01-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2374854C (en) | Random access control method and system | |
| US6574212B1 (en) | Transmission of random access bursts with at least one message part | |
| EP3654671B1 (en) | Communication system, mobile station, base station, response decision method, resource configuration decision method, and program | |
| EP1159848B1 (en) | Improved message access for radio telecommunications system | |
| US6859441B2 (en) | Random access channel access and backoff mechanism | |
| EP2326134B1 (en) | Method and apparatus for controlling transmission parameters on a random access channel | |
| EP0578703B1 (en) | A method of controlling the operation of a packet switched cdma telecommunication network | |
| WO2001097411A1 (en) | Method of assigning an uplink random access channel in a cdma mobile communication system | |
| AU1952800A (en) | Process for controlling uplink packet transmission in a wireless communication system | |
| CA2423913A1 (en) | Mobile-assisted network based techniques for improving accuracy of wireless location system | |
| KR20050096201A (en) | Method for providing fast feedback information for random access channel in a wireless communication system | |
| AU733372B2 (en) | Common channel communication device and method supporting various data rates in mobile communication system | |
| JP2000358281A (en) | Method for controlling access to radio resources for transmitting incoming link packet in radio communication network | |
| KR101588047B1 (en) | A method for signalling random access channels | |
| JP4611965B2 (en) | Random access control method and system | |
| AU2002216741A1 (en) | Contention access control system and method | |
| JP2001503219A (en) | Transmission timing offset method for DS-CDMA mobile telephone system | |
| JP2001128235A (en) | Wireless network with a plurality of duration possibilities to access random access channel | |
| EP3179817A1 (en) | Information transmission method, user side device and network side device | |
| KR100311524B1 (en) | Transmission Method for status information of Common Packet Channel | |
| KR100662267B1 (en) | Method for Allocating CPCH and Apparatus for Transmitting/Receiving to Receive Packet through CPCH | |
| Niththiyanathan et al. | Performance analysis of the random access procedure in WCDMA | |
| KR20020053953A (en) | Traffic Control Method of Random Access Channel in Asynchronous Wireless Communication System |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20190527 |