WO2004045125A2

WO2004045125A2 - Hybrid wired/wireless local area networking

Info

Publication number: WO2004045125A2
Application number: PCT/US2003/034998
Authority: WO
Inventors: James A. Crawford
Original assignee: Magis Networks, Inc.
Priority date: 2002-11-07
Filing date: 2003-11-03
Publication date: 2004-05-27
Also published as: WO2004045125A3; AU2003286880A8; AU2003286880A1

Abstract

Hybrid wireless/wired networks providing a wireline extension of a wireless transmission in order to fill in poor coverage regions and/or increase signaling range without increasing transmit power levels or decreasing data rates. In one implementation, a hybrid network (200) includes a communication terminal (102) for communicating wirelessly with each of a plurality of remote communication terminals (106) of a wireless network, the communication terminal functioning as an access point. The network also comprises an antenna (104) coupled to an output of the communication terminal for wirelessly transmitting signaling to the remote communication terminals; and a wireline extension (204) coupled to the output of the communication terminal for transmitting the signaling via the wireline extension a distance to a remote location. In preferred implementations, the network communicates using OFDM in which additional multipaths are added over at least a portion of a wireline.

Description

HYBRID WIRED/WIRELESS LOCAL AREA NETWORKING

BACKGROUND OF THE INVENTION

1. Field of the Invention The present invention relates generally to wireless networks, and more specifically to wireless local area networks. Even more specifically, the present invention relates to providing reliable communication within a wireless local area network.

2. Discussion of the Related Art

Conventional wireless local area networks (wireless LANs or WLANs) are increasing in popularity for home and business use. As illustrated in FIG. 1, a conventional wireless LAN 100 or wireless network 100 includes a communication terminal that functions as an access point 102 (illustrated as AP) having an antenna 104. The network 100 also includes multiple remote communication terminals 106 (illustrated at RTs) each having an antenna 108 that communicate wirelessly with the access point 102. The access point 102 typically functions as a gateway to a larger network, for example, a computer network such as the internet, via a cable fiber network or via a public switched telephone network (PSTN). The remote terminals 106 may be fixed in location or mobile within the coverage area 110 of the network 100; however, it is desired that the access point 102 be able to reliably communicate with a remote terminal 106 located anywhere within the given coverage area 110. However, depending on the physical layout within the coverage area 110, there may be poor coverage regions within the coverage area. For example, coverage fall-outs could occur due to significant metal content in walls and floors, or simply due to unusually high signal attenuation due to wall-mounted fixtures, cabinets, etc. that make full throughput wireless communication links marginal. Furthermore, high quality of service (QoS) downlink communications from the access point 102 to the remote terminals 106 which are transmitted using a high data rate require a high signal-to-noise ratio (SNR) at the remote terminals 106 to be reliably received.

One solution to provide better coverage within a poor coverage region and to provide an increased SNR at a given remote terminal would be to increase the transmit power level of the access point 102. However, this presents a problem in dense user deployment situations like apartments and condominiums, which leads to a sizeable footprint increase of the coverage area 110 that interferes with the re-use of that particular radio frequency channel until distance and signal absorption reduce the signal level down to roughly the natural noise level of the environment. Another solution would be to lower the data rate of the signaling to a more robust level; however, this solution is not practical when delivering high quality of service traffic that is only useful if received timely.

SUMMARY OF THE INVENTION The invention advantageously addresses the needs above as well as other needs by providing hybrid wired/ wireless local area networks that are capable of both wireless and wired communications.

In one embodiment, the invention can be characterized as a hybrid wireless/ wired network comprising a communication terminal for communicating wirelessly with each of a plurality of remote communication terminals of a wireless network, the communication terminal functioning as an access point of the wireless network. The network also comprises a first antenna coupled to an output of the communication terminal for wirelessly transmitting signaling to the plurality of remote communication terminals; and a wireline extension coupled to the output of the communication terminal for transmitting the signaling via the wireline extension a distance to a remote location.

In another embodiment, the invention can be characterized as a method for use in a wireless network comprising the steps of: transmitting signaling from a communication terminal to a plurality of remote communication terminals via a wireless communication medium, the wireless communication medium providing a plurality of multipaths, wherein one or more of the plurality of remote communication terminals receives multiple reflections of the signaling within a nominal window of time, the communication terminal configured to function as an access point of the wireless network; and transmitting the signaling from the communication terminal to a remote location a distance from the communication terminal via a wireline extension.

In a further embodiment, the invention may be characterized as a hybrid wireless/ wired network comprising: a communication terminal configured to communicate wirelessly with each of a plurality of remote communication terminals of a wireless network over a wireless communication medium, the communication terminal configured to function as an access point of the wireless network. The plurality of remote communication terminals are coupled to the communication terminal via wireline and the communication terminal transmits signaling formatted for wireless transmission to the plurality of remote communication terminals via the wireline.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings.

FIG. 1 is a diagram of a conventional wireless local area network illustrating an access point communicating with multiple remote terminals within a network coverage area.

FIG. 2 is a diagram of a hybrid wireless/ wired local area network according to one embodiment of the invention in which the transmit output of an access point is transmitted via the wireless communication medium and also via a wireline extension to a remote location for filling in poor network coverage and to provide network range extension.

FIG. 3 is a block diagram of an orthogonal frequency division multiplexed (OFDM) communication terminal including a transmitter portion and a receiver portion according to one embodiment of the invention, which is implemented in an access point and in each of multiple remote terminals of the hybrid network of FIG. 2.

FIG. 4 is a timing diagram of a conventional OFDM communication burst transmitted in to a frame structure according to the IEEE 802.11a standard. FIG. 5 is a block diagram of a splitter module located at the access point of the hybrid network of FIG. 2 in accordance with one embodiment.

FIG. 6A is a block diagram of one embodiment of an extension module coupled to the wireline extension of FIG. 2 at a remote location that transmits wireless communications to one or more remote terminals of the hybrid network of FIG. 2.

FIG. 6B is a block diagram of one embodiment of an extension module coupled to the wireline extension of FIG. 2 that transmits and receives wireless communications to and from one or more remote terminals of the hybrid network of FIG. 2.

FIG. 7 is a diagram of a hybrid wireless/ wired local area network according to another embodiment of the invention including wireless remote terminals and one or more wired remote terminals that communicate with the access point via a wireline connection. FIG. 8 is a block diagram of one embodiment of an extension module coupled to the wireline extension of FIG. 2, the extension module transmitting and receiving wired communications to and from one or more wired remote terminals of the hybrid network of FIG. 7.

FIG. 9 is a block diagram of a variation of the hybrid wireless/ wired network of FIG. 7 in which one or more remote terminals communicate with the access point via the wireline extension and also simultaneously communicate with the access point wirelessly providing a hot swappable remote terminal.

FIG. 10 is a splitter module coupled to the transceiver of the hot swappable remote terminal of FIG. 9 that allows wireless and/ or wired communications with the access point.

FIG. 11 is a block diagram of an access point of a hybrid wireless/ wired network in which wireless communications and wired communications are transmitted from and received at the access point at different frequencies in accordance with another embodiment of the invention.

FIG. 12 is a diagram of a hybrid wireless/ wired local area network according to yet another embodiment of the invention in which a wireless access point designed to communicate wirelessly with a plurality of remote terminals is coupled to and communicates with its remote terminals via wireline connections.

Corresponding reference characters indicate corresponding components throughout the several views of the drawings.

DETAILED DESCRIPTION

The following description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the preferred embodiments. The scope of the invention should be determined with reference to the claims. Several embodiments of the invention provide a hybrid wireless/ wired local area network which transmits signaling from an access point to remote terminals via a wireless communication medium or link while at the same time transmits the same signaling through a wireline extension path that directs the signaling to one or more remote terminals that otherwise may have difficulty receiving the signaling via the wireless communication medium due to their location in a poor coverage region or to their location outside of the coverage area. Thus, in one embodiment, the hybrid wireless/ ired network fills in poor coverage regions of the coverage area of the wireless network without increasing the access point transmit power level and/ or reducing the data rate of the signaling. Additionally, according to some embodiments, different levels of range extension are possible which increase the effective coverage area without increasing the transmit power level or reducing the data rate or throughput of the signaling. Thus, the coverage footprint of the hybrid wireless/ wired network is not increased, which reduces interference and allows frequency reuse in neighboring wireless networks, in order to reliably communicate with remote terminals that are within poor coverage regions or are otherwise outside of the nominal access point coverage area. Such hybrid networks are particularly useful in convergent products, such as cable set top boxes that include both wireless and wireline functionality, although traditional wired and wireless solutions are separate from each other.

Referring to FIG. 2, illustrated is a hybrid wireless/ wired local area network 200 (hereinafter referred to as hybrid network 200 or simply network 200) including an access point 102 (hereinafter AP 102) having an antenna 104. The hybrid network 200 also includes multiple remote terminals 106 (illustrated individually as RT 106A, RT 106B, RT 106C, RT 106D and RT 106E) each having an antenna 108. Similar to the conventional wireless network 100 of FIG. 1, the AP 106 communicates in a downlink to each RT 106 and each RT 106 communicates in an uplink back to the AP 102 via a wireless communication medium (also referred to as a wireless channel or link). These communications or signaling are illustrated as waveforms extending from the respective antennae. It is noted that the AP 102 is referred to generically as a "communication terminal" and each RT 106 may be referred to as a "remote communication terminal". It is also noted that the remote terminals are labeled individually to better describe several features of this embodiment of the invention. Typically, AP 102 serves as a gateway to a larger network, for example, a computer network such as the internet, via a cable fiber network or via a public switched telephone network (PSTN). The RTs 106 may be fixed in location or mobile; however, in order for the AP 102 to reliably communicate with the RTs 106 via the wireless communication medium, the RTs must be located within the coverage area 110 of downlink communications from the AP 102.

It is noted that the size of the coverage area 110 (i.e., the range of the signaling) is variable depending on the type of signaling transmitted, the transmit power level and the data rate or throughput (which is dictated by the quality of service (QoS) of the signaling). In one example, the higher the transmit power level, the larger the coverage area 110, which increases interference in neighboring networks in a dense deployment. Also, the higher the quality of service of the signaling (i.e., the higher data rate that is required), more SNR is required at the receiving terminal in order to reliably receive the signaling. For example, a signal having a data rate of 6 Mbps (e.g., modulated using BPSK and having an encoding rate of Vi) may require approximately -94 dBm at the receiving terminal for a bit error rate (BER) of 10" , while a signal having a data rate of 54 Mbps (e.g., modulated using 64- QAM and having an encoding rate of ³/_) may require approximately -74 dBm at the receiving terminal for the same BER. That is, the higher data rate signaling requires a 20 dB increase in SNR. Therefore, the range of the higher data rate signal a distance corresponding to 20 dB less than the range of the lower data rate signal. Thus, the higher the data rate given a fixed transmit power level, the less the coverage area. In many wireless networks, the wireless communication link is asymmetric, i.e., one of the downlink or the uplink requires a higher data rate than the other. For example, in a home wireless network that delivers high QoS signaling to a remote terminal in a downlink direction, but transmits small amounts of control and acknowledgement data in the uplink, the overall coverage area 110 is dictated by the disadvantaged link, in this case, the downlink. For example, the access point 102 may transmit a high quality of service digital video signal (e.g., a high definition digital television signal) in the downlink direction, but the uplink only transmits control data back to the AP 102. The remote terminals 106 will require more SNR than that required at the access point 102 to reliably receive the signaling. One way to increase the coverage area 110 to compensate for high data rate signaling would be to increase the transmit power level of the AP 102; however, in dense deployments, such as apartment buildings and offices, this causes interference in adjacent wireless networks. In response, in order to better receive their own signaling, an adjacent network may increase its transmit power levels, which causes a further degradation of the signaling in the first wireless network.

Another problem involves poor coverage regions within the coverage area, for example, regions in which there is significant metal content or other structure to limit reliable reception of the wireless signal at the given transmit power level and data rate. Again, the transmit power level may be boosted until the remote terminal in the poor coverage region is able to reliably receive the communications; however, this causes interference in neighboring networks. Alternatively, the data rate may be lowered; however, this is not an option for high quality of service signaling.

To avoid these problems of conventional wireless networks, such as wireless network 100 of FIG. 1, as illustrated in FIG. 2, the hybrid network 200 provides a splitter module 202 that couples a transmit output of the AP 102 to the antenna 104. The splitter module 202 inputs the AP transmit output, i.e., the signaling to be transmitted to the remote terminals 106 and outputs the signaling to both the antenna 104 and to a wireline extension 204. Similarly, depending on the embodiment, the splitter module 202 combines uplink signaling received from the antenna 104 and, depending on the embodiment, uplink signaling received from the wireline extension 204 to a receive input of the AP 102. One embodiment of a splitter module 202 is illustrated in FIG. 5. The wireline extension 204 extends a distance away from the AP 102 to a remote location. The wireline extension 204 comprises one or more wirelines used as a wired communication medium for the signaling from the AP. In preferred embodiments, the wireline extension 204 comprises an existing coaxial cable plant of a home or business including various sections of coaxial cable and passive splitters. The cable plant may be easily accessible to the user via existing cable jacks or additional cable jacks may be added by the user. The wireline extension 204 may be split into numerous portions.

For example, in the illustrated embodiment, the extension wireline 204 is coupled to a passive splitter 206 that further splits the signaling to various branches of the wireline extension 204. In one branch, the wireline extension 204 is coupled to an extension module 208 at a remote location relative to the AP 102, the extension module 208 having an antenna 210. In this embodiment, the extension module 208 is a transmitting device that functions to wirelessly transmit the signaling generated at the AP 102 to a given remote terminal, e.g., RT 106C. However, rather than transmitting the signaling from the location of the access point 102, the extension module 208 transmits the signaling from the remote location at antenna 210. One embodiment of an extension module 208 is illustrated in FIG. 6A.

The extension module 208 advantageously provides an additional point or location of transmission, which may be used to fill a potentially poor coverage region within the coverage area 110. For example, in this embodiment, RT 106C is located in a poor coverage region within the coverage area 110 and is unable to reliably receive the downlink signaling from AP 102 given the transmit power level and the data rate, i.e., there may be significant metallic structures or other reflecting surfaces separating the AP 102 from RT 106C. Rather than increasing the transmit power level or decreasing the data rate or throughput of the downlink signaling, at the same time the downlink signaling is transmitted from the antenna 104, it is also transmitted to the extension module 208 and then wirelessly transmitted to any proximate remote terminals, e.g., RT 106C, via antenna 210. Thus, if the remote terminal can not reliably receive the signaling from antenna 104, it can reliably receive the signaling from antenna 210. Thus, according to one embodiment, a hybrid wired/ wireless network 200 is provided that fills in poor coverage regions without increasing the access point 102 transmit power level and/ or reducing the data rate or throughput of the signaling. It is noted that in this embodiment, uplink communications from the remote terminal 106C back to the AP 102 occur over the wireless communication medium, since the uplink communications are generally at the most robust data rate. For example, in one embodiment, the downlink signaling may be at a date rate 54 Mbps using 64-QAM, while the uplink signaling may be at a date rate of 6 Mbps using BPSK. In the other branch of the passive splitter 206 of FIG. 2, the wireline extension 204 is coupled to a range extension module 212 located at another remote location and having an antenna 214. The range extension module 212 functions to transmit the downlink signaling from AP to one or more RTs, e.g., RT 106D and 106E, that are out of the coverage area 110 of the downlink signaling or communications of the AP. For example, at the same time the signaling is transmitted from the antenna 104, it is also transmitted via the wireline extension 204 to the range extension module 212 and then wirelessly transmitted to any proximate remote terminals, e.g., RTs 106D and 106E, via antenna 214. In this embodiment, the remote terminals receiving communications from the extension module 212 are out of the coverage area 110 for signaling from the access point 102 at a given transmit power level and a given data rate. However, the extension module 212 allows them to receive communications from the access point 102 as if they were within the coverage range 110 of the access point 102. Additionally, since these remote terminals are outside of the coverage area, they communicate uplink signaling back to the access point 102 via the range extension module 212 at the remote location. That is, the range extension module 212 includes both transmit and receive functionality. The range extension module 212 includes a power amplifier to boost the TX signal and a low noise amplifier to boost the received signal so that it can be transmitted back to the access point 102 without too much attenuation over the wireline extension 204. The uplinks signals from RTs 106D and 106E are relayed back to the access point 102 via the wireline extension 204 and the splitter module 202 which combines the uplink communications from RT 106D and RT 106E with uplink communications from the other remote terminals (possibly including RT 106D and 106E) received via antenna 104. One embodiment of the range extension module 212 is illustrated in FIG. 6B. It is noted that the range extension module 212 may optionally only include transmit functionality if the access point is still within range of the uplink signaling.

This second branch of the passive splitter 206 provides for large scale network range extension. For example, depending on the signal attenuation through the wireline extension 204, the range extension module 212 may be located at various distances from the access point 102. For example, in embodiments, where the wireline extension 204 is an existing cable plant, the range extension module 212 may be located 1000-2000 feet from the access point 102, such as in a guest house or garage. For example, a 75 ohm coaxial cable of reasonably good quality, such as RG-6, provides signal attenuation of about 10 dB per 100 feet of length for a 5 GHz signal. In one case, a 40 dB amplification provides that the range extension module 212 may be located up to about 400 feet from the access point. Thus, the amplification at the range extension module 212 helps to dictate the distance that the range extension module 212 may be located from the access point 102. It is noted that the remote terminals RT 106D and 106E may actually be within range for uplink communications to the AP 102, since the uplink communications may be at a lower data rate than the downlink communications. Thus, the range extension module 212 may only require TX functionality and not RX functionality. In these embodiments, the range extension module 212 provides full throughput downlink range extension out to the range of the uplink communications. Thus, downlink signaling range is effectively increased to more closely match the uplink signaling range without having to increase the downlink transmit power level or decrease the downlink data rate.

Such a hybrid network 200 represents a departure from known wireless networks 100 in that a portion of the wireless transmission is transmitted via a wireline segment; thus, creating a hybrid wireless/ wired network. Known networks are either all wired or all wireless. Even in convergent technologies, such as in a set top box, a separate solution is used for wireless transmissions and wired transmissions. In contrast, the wireless solution is used to transmit signaling via both wireless and wireline mediums. Furthermore, according to many embodiments, the wireline segment is provided by an existing cable plant of the home or business, adding very little complexity to the network.

Advantageously, in one embodiment, the network 200 communicates using a Time Division Multiple Access/ Time Division Duplex (TDM A/ TDD) scheme such that each terminal (the AP and the RTs) within the network 200 is allotted a specified time period within which to transmit and receive. This allows the multiple users to transmit and receive without interfering with each other. The hybrid network 200 may communicate using any known wireless networking technique. In preferred embodiments, the network 200 uses orthogonal frequency divisional multiplexed (OFDM) communications based on the IEEE 802.11a standard or the HiperLAN2 standard. However, the wireless network 200 may communicate using frequency hopping spread spectrum (FHSS) or direct sequence spread spectrum (DSSS), for example, using the IEEE 802.11, 802.11b or 802.11g standards, or any other known wireless protocol accepted for use in indoor/ outdoor wireless networks. Thus, a wireless network 200 in accordance with the invention may use any suitable single carrier or multicarrier (one example of which is OFDM) transmission scheme; however, multicarrier schemes are preferred due to their ability to deal with the multipath channel.

In some embodiments, the hybrid network 200 is a residential network in which the access point 102 is to another computer network, for example, a cable or satellite interface to an Internet, while the remote terminals comprise computers (PCs), laptops, televisions (e.g., high definition televisions), stereos, appliances, palm devices, appliances, etc. In other embodiments, the network 200 comprises a wireless local area network in an office or business in which the access point 102 couples to a larger computer network and the remote terminals comprise other computers, laptops, palm devices, televisions, appliances, etc. Thus, the data transmitted may represent simple data, audio, video, etc. It is understood that the wireline extension 202 of the wireless network 100 to form a hybrid wireless/ wired network 200 of several embodiments of the invention may apply to any wireless communication network in which there exist regions of poor coverage or a desire to communicate with terminals outside of the coverage area of downlink and/ or uplink communications. It is noted that in many embodiments of the invention, one or more of the remote terminals 106 support communications requiring a different SNR, i.e., one or more of the remote terminals support traffic of different types of service (TOS). For example, one or more of the remote terminals 106 may support one or more of data, voice, and video traffic, for example.

Multicarrier communications, such as OFDM-based communications, are preferred due to their inherent tolerance of the severe multipath characteristics of the indoor/ outdoor wireless communication medium. As is well known in the art, according to OFDM communications, a signal is transmitted within a very short period of time and is transmitted over multiple carriers at the same time. During propagation, the multiple subcarriers are variously reflected and received. However, the OFDM signal includes a guard time interval such that all reflections of a given signal will have sufficiently decayed prior to transmitting the next signal. The receiving terminal is able to align the various carriers and extract the transmitted data.

In many embodiments of the invention, OFDM's use of multiple carriers is exploited to intentionally provide additional multipath communications. For example, when a given signal is transmitted from antenna 104 to the remote terminals 106 within the coverage area 110, that signal is reflected and received within a window of time including the guard time interval as several different versions of that signal at the receiver. At substantially the same time that the signal is transmitted from antenna 104, the signal is also transmitted via the wireline extension 204 to the extension module 208 at a remote location, which then transmits the downlink signal to one or more remote terminals, e.g., RT 106C. The signal transmitted to RT 106C is also reflected. However, from the viewpoint of RT 106C, it receives what it perceives as additional reflections of the signal transmitted from antenna 104. Thus, the receiver of RT 106C does not know or care where the additional reflections came from, it simply processes them as if they were all reflections of the originally transmitted signal that came from antenna 104. Advantageously, the signaling transmitted from the extension module 208 arrives at the RT 106C during the window of time that the remote terminal expects signaling to be received from antenna 104, i.e., within the period of time including the guard time interval. In one example, a 100 foot section of RG-59U cable has a propagation factor of about 0.70 such that a signal transmitted thereover will take approximately 43% longer to reach the RT 106C, than for a wireless transmission from antenna 104. This translates to about a 43 ns delay for receipt of signals from the extension module 208 compared to receipt of signals directly from the antenna 104; however, this delay is negligible due to the 0.8 μs guard time interval.

If RT 106C where unable to reliably receive the signal from antenna 104 due to its location in a poor coverage region of the coverage area 110, RT 106C would receive the signal from the extension module 208 as if it was transmitted from antenna 104. Thus, the extension module 208 effectively fills in poor coverage regions without having to increase the transmit power level or decrease the data rate. In many cases, decreasing the data rate is not an option that could improve poor coverage areas depending on the quality of service of the signaling being transmitted. For example, a high definition video signal or a video conferencing signal would be of little use if its transmission was slowed or delayed. Increasing the transmit power level until RT 106C could receive the signal from antenna 104 may solve the problem, but this raises interference concerns, particularly in a dense deployment. Additionally, the remote terminal 106 may be surrounded by sufficient metal that remote terminal can not reliably receive the signaling even at the highest transmit power level.

Additionally, if RT 106C were to have marginal reception of the signal for antenna 104, such that both the signal transmitted from the antenna 104 and the signal transmitted from the extension module 208 was received at the remote terminal 106, the receiver would simply choose the strongest or most consistent signal, regardless of its transmission source (i.e., antenna 104 or 210). For example, if RT 106B were to also receive the signal from the extension module 208, RT 106B would simply select best signal for communications, whether it was actually transmitted from antenna 104 or antenna 210. It is further noted that in preferred embodiments of the wireless network 200 of FIG. 2, the wireless link is asymmetric in that the downlink communications are high quality of service signals (e.g., sent using 16-QAM or 64-QAM), while the uplink is low data rate control signaling, such as acknowledgement, forward error correction, etc. Such acknowledgement signaling is commonly sent using the most robust signaling rate, e.g., BPSK. Thus, even though RT 106C can not reliably receive signals from AP 102, AP 102 can reliably receive uplink signals from RT 106C. Thus, in this embodiment, the extension module 208 does not include receive functionality, although it may include receive functionality in other embodiments. It is also noted that the wireless network 200 may be such that the uplink is the disadvantaged link.

According to many embodiments, the extension wireline 204 may be implemented by simply splitting the transmit output of the access point 102 such that at the same time the access point 102 transmits the signaling via antenna 104, the same signaling is relayed or transmitted via the wireline extension 204 to a remote location. At the remote location, for example, an extension module, e.g., modules 208 and 212, transmit the signaling to one or more remote terminals. The splitter module 202 simply functions to route the transmit output to the transmit antenna 104 and to a remote location, while passive splitter 206 functions to split the transmit output to additional remote locations. The extension modules 208 and 212 function as repeaters. It is noted that an amplifier should be used at each extension module 208 and 212 to amplify the signal to be wirelessly transmitted due to attenuation of the signaling as it travels the extension wireline 204. The amount of amplification should vary depending on the length and type of the wireline extension.

In preferred embodiments, wired extension of the wireless network can be easily added to an existing wireless network 100, by minimally providing the splitter module 202 and an extension module 208, 212. If the existing coaxial cable plant or coax wiring of the home or business is used, the wireline extension 204 is already provided. For example, in a home use application, the access point is formed within or coupled to a cable set top box (STB). The transmit output of the access point 102 would be coupled to its antenna and also be connected to any cable connection within the home, preferably, as provided by the STB. As such, an extension module may be connected to any cable interface of the cable plant within the home using known connectors. In its simplest form, the extension module 208 includes a low power amplifier and an antenna. For example, as a user experiences poor reception at a given remote terminal, such as a high definition television located in another room away from the STB, the user may connect an extension module 208 to an unused cable outlet of the other room in order to fill in the region of poor coverage in the other room, without requiring that the access point increase its transmit power level or decrease its data rate. This extension module is also designed to be low power relative to the access point 102, so that it does not cause interference with any adjacent wireless networks.

It is noted that in embodiments in which the wireline extension 204 comprises the existing cable plant of the home or business, other signals may also be transmitted over the cable plant, such as a conventional cable television signals or internet traffic. However, such traffic is at conventional wireline frequencies. For example, conventional digital cable signals are sent using 64-QAM or 256-QAM in a 6 MHz bandwidth at about 50-550 MHz. In contrast, preferred signaling transmitted via the wireless communication medium and the wireline extension 204 are transmitted using from BPSK to 64-QAM at approximately 5 GHz ( 5.15-5.35 GHz), for example, according to that allowable in the IEEE 802.11a standard. Thus, the signaling provided according to several embodiments of the invention is on top of and transparent to existing traffic on the existing cable plant. In preferred embodiments, the network 200 is designed to deliver high quality of service performance suitable to support a wide range of data, video and audio applications. The physical layer is similar to the IEEE 802.11a standard, utilizing the 5 GHz frequency bands and channelization, orthogonal frequency division multiplex (OFDM), 48 data- bearing subcarriers with 4 pilot subcarriers, a 0.80 μs guard interval, etc. The physical layer is specifically designed for the wireless multipath channel. The typical maximum transmit power levels used range from +16 dBm up to as high as +23 dBm as dictated by the FCC for the lower 5 GHz bands (5.15 - 5.35 GHz). Wireless propagation pathloss as high as 97 dB to 117 dB can therefore be tolerated depending upon the data throughput rate being supported. In one embodiment, the access point 102 communicates using constellations of BPSK, QPSK, 16-QAM and 64-QAM; encoding rates of 1/2, 2/3 and 3/4; and data rates or throughput of 6-54 Mbps. The following describes the basic structure of an OFDM communication terminal for such use in the network 200 according to one embodiment.

Referring next to FIG. 3, a functional block diagram is shown of a known orthogonal frequency division multiplexed (OFDM) communication terminal implemented at one or more of the access point 102 and the remote terminals 106 according to several embodiments of the invention. The terminal 300 including both a transmitter portion 302 and a receiver portion 304. The transmitter portion 302 includes input data from a medium access control (MAC) layer, a baseband modulator and forward error correction (FEC) 308, an inverse fast Fourier transform 310 (hereinafter referred to an inverse FFT 310 or simply IFFT 310), a cyclic prefix extension 312, a preamble insertion 314, an IQ modulator 316 (also referred to as an RF modulator), an upconverter 318 and a transmit (TX) output to go to a TX antenna (not shown). The receiver portion 304 includes a receive (RX) input from a RX antenna (not shown), a downconverter 320, an IQ demodulator 320 (also referred to as an RF demodulator), a cyclic prefix removal 324, a preamble detector 326, a fast Fourier transform 328 (hereinafter referred to as FFT 328), a baseband demodulator and FEC 330, and output data to the MAC. The communication terminal 300 generally includes a baseband processing portion 332 which may be implemented as a baseband integrated circuit device or chip and a radio frequency (RF) portion 334 that may be implemented as an RF integrated circuit device or chip.

Referring briefly to FIG. 4, a diagram is shown of the PHΥ-layer frame structure according to the IEEE 802.11a standard used in orthogonal frequency division multiplexed (OFDM) communications. The frame 400 (also known as a PHY-layer frame or a medium access control (MAC) frame) includes a preamble portion 402 and a data portion 404. The preamble portion 402 includes a short symbol portion 406 including short symbols and a long symbol portion 408 including long symbols. The short symbol portion 406 is used for signal detection, automatic gain control (AGC), diversity selection, coarse frequency offset estimation, and timing synchronization. The long symbol portion 408 is used for channel estimation and fine frequency offset estimation.

The data portion 404 includes multiple data symbols 410 (also referred to as OFDM symbols 410 or generically referred to as "signals"), each symbol 410 having a data region 414 and a guard time interval 412 preceding the data region 414. The guard time interval 412 is utilized to allow the wireless communication channel's transient to decay before transmitting the next OFDM symbol 410. According to the IEEE 802.11a standard, this guard time interval 412 is 0.8 μs and the data region 414 length is 3.2 μs, such that the data symbol 410 is 4 μs. As such, the guard time interval 412 is long enough such that all reflections of the transmitted symbol 410 (particularly the data region 414 of the transmitted symbol 410) through the multipath wireless communication medium are adequately reduced prior to reception of the next OFDM symbol 410.

Referring back to FIG. 3, the following discussion describes a wireless LAN application using OFDM modulation under the IEEE 802.11a standard having the frame 400 of FIG. 4 to describe several embodiments of the invention. The input data from the MAC that is to be transmitted to one or more communication terminals within the wireless network is input into the baseband modulator and FEC 308 which modulates the data into digital baseband signals, i.e., I and Q signals. For example, the baseband modulator 308 may use, but is not limited to, binary quadrature phase shift keying (BPSK), quadrature phase shift keying (QPSK), or quadrature amplitude modulation (QAM). These digital baseband signals are input to the IFFT 310 which transforms the frequency domain digital baseband signals to time domain digital baseband signals. These signals are coupled to the cyclic prefix extension 312, which adds a guard time interval 412 at the beginning of each OFDM data symbol 410. This guard time interval 412 is an extension of the tail of each data region 414 that is made to precede each data region 414. Advantageously, as described above, this guard time interval 412 is purposely made longer than the time it takes for the transient due to reflections for a particular data symbol 410 to decay prior to the reception of the next OFDM data symbol.

Next, the digital baseband signals are coupled to the preamble insertion 314, which inserts an appropriate preamble portion 402 in front of the data portion 404. Next, the OFDM signal is modulated by the IQ modulator 316 and upconverted to radio frequency (RF) as a plurality of subcarriers each having a different center frequency by the upconverter 318. The output of the upconverter 318 is the TX output and is coupled to a transmit antenna, e.g. antenna 104 or antenna 108. Advantageously, according to many embodiments, the TX output is also coupled to a wireline extension via the splitter module 202. Thus, the same TX output that is specifically formatted for wireless transmission is simultaneously transmitted via wireline through the wireline extension 204.

A receiving terminal, such as a remote terminal 106 also includes the components of FIG. 3. The transmitted signaling received from the RX antenna is downconverted at the downconverter 320 and demodulated to baseband at the IQ demodulator 128. Next, the baseband signal is coupled to the preamble detector 326 and the cyclic prefix removal 324. The preamble detector 326 conventionally uses an autocorrelation algorithm which detects the presence of the signaling, estimates the frequency error of the received signaling, and also synchronizes with the timing of the preamble. The cyclic prefix removal 324 removes the guard time interval 412 that was inserted at the cyclic prefix extension 312 of the transmitter portion 302. As such, the guard time interval 412 accounts for normal time dispersion of the symbol which is introduced by the multipath channel. This time-windows the received signaling into discrete windows of time, each containing one OFDM data region 414.

Next, the time- windowed digital baseband signal is input to the FFT 328, which converts the time domain digital baseband signal into its equivalent frequency domain digital baseband signal. Next, the signal is demodulated and checked for errors in the baseband demodulator and FEC 330. The output is sent is then sent as data received to the MAC.

It is noted that the block diagram of FIG. 3 represents the basic structure of the baseband processing and RF portion of an OFDM communication terminal. However, it is noted that additional signal processing components may be included, such as scramblers, coders, interleavers, etc., as are well known in the art.

In a typical wireless local area network application, the communication terminal 300 comprising an access point, e.g., AP 102, is coupled to a cable set top box or other data source. Such as access point is designed to wirelessly communicate with one or more remote communication terminals, e.g. RTs 106, forming the wireless network, e.g., network 100 or 200. Each of the remote terminals 106 also includes the same basic OFDM communication terminal 300 structure. However, the receive input of the remote terminal 106 is coupled to the specified device that is to communicate with the access point, such as a computer, high definition television, audio equipment, and appliance, for example. Thus, the OFDM communication terminal 300 represents one example of the basic wireless communicating structure for devices in the wireless network that communicates using OFDM. It is also understood that the communicating devices may communicate using other single carrier (such as FHSS or DSSS) or multicarrier transmission schemes; however, in preferred embodiments, an OFDM transmission scheme is used since it is well adapted to handle the harsh multipath environment of the indoor/ outdoor wireless communication medium. As described above, in accordance with several embodiments of the invention, at the access point, the TX output is coupled to the splitter module 202 which couples the modulated and upconverted TX output to both the antenna 104 and the wireline extension 204. This is in contrast to known wireless networks, which only transmit the wirelessly modulated and converted signal over the wireless communication medium. According to the invention, the TX output that is formatted for wireless transmission is also transmitted via the wireline extension 204. One of ordinary skill in the art could easily transmit a wireless TX output via a wireline; however, there is no reason to do so in known wireless networks. If one wished to transmit the data via a wireline as is known in the art, there would be no need for such a complex transmission system based on a multicarrier transmission scheme (such as OFDM using 48 subcarriers) that is specifically designed for the harsh multipath wireless communication medium. In the known art, a wireline solution designer would simply choose a single carrier transmission scheme and transmit using even higher data rates (such as, by using 256- QAM), such as those currently available for wireline transmission since multipaths are negligible through a wireline. The known art provides a separate solution for wireless communications.

From the receiver portion 304, all signals received at the receive antenna, e.g., antenna 108, comprise the RX input and are coupled to the downconverter 320 regardless of their actual source of transmission. Thus, the receiver portion 304 of the remote terminals 106 receives reflections of the signaling transmitted from antenna 104 and antenna 210. However, the receiver portion 304 will select the strongest signaling. In one variation including receive antenna diversity, as is known in the art, the receiver may receive the signaling from multiple receive antennas, a respective receive antenna having the strongest signal being coupled to the downconverter 320 via a switch (not shown). In addition to the multiple antenna signals, such diversity selection could also input the signaling received via the wireline extension 204 as an additional diversity path. Additional details describing one implementation using diversity antenna selection may be found in U.S. Patent Application No. 09/994,519, of Crawford, et al, filed November 26, 2001, entitled METHOD FOR ESTIMATING CARRIER-TO-NOISE-PLUS- INTERFERENCE RATIO (CNIR) FOR OFDM WAVEFORMS AND THE USE THEREOF FOR DIVERSITY ANTENNA BRANCH SELECTION.

Referring next to FIG. 5, a block diagram is shown of a splitter module located at the access point of the network of FIG. 2 in accordance with one embodiment. The TX output of the access point 102 (e.g., the TX output of the transmitter portion 302) is input to a coupler 502. The coupler 502 splits the TX output to a transmit antenna 104A via wireline 504. The coupler 502 also splits the TX output to a power amplifier 506. The power amplifier 506 boosts the power level of the output signal to account for losses through the coupler 502, which may be about 10-20 dB, e.g., in one embodiment, the signal is boosted by the power amplifier 506 to level of about +17 dBm. The output of the amplifier 506 is coupled to the wireline extension 204 via combiner 508. Thus, the TX output of the access point 102 is coupled to both the antenna 104A for wireless transmission to the remote terminals, and also coupled to the wireline extension 204 for parallel transmission through the wireline extension 204 to a remote location. Additionally, the RX input received from a RX antenna 104B is coupled to combiner 510 via wireline 512. Combiner 510 also receives any RX input signaling received from the wireline extension 204 through combiner 508. The output of combiner 510 comprises the RX input signal that is input to the access point 102 (e.g., input to the downconverter 320 of the receiver portion 304). It is noted that in embodiments employing antenna receive diversity, multiple RX antennas may be coupled to the combiner 510. In such embodiments, a diversity selection module would select which of the diversity antenna signals to receive. Such a selection module could include the receive input from the wireline extension 204 as an additional diversity path in selecting the strongest path to couple to the downconverter 320.

It is also noted that although two different antennas 104A and 104B are illustrated, in other embodiments, there may be a single antenna. A switching device should be included to switch the TX output and the RX input to the single antenna. Referring next to FIG. 6 A, a block diagram is shown of one embodiment of an extension module 208 coupled via wireline to the splitter module 202 of FIG. 5 that transmits wireless communications to one or more remote terminals of the hybrid network of FIG. 2. The wireline extension 204 is coupled to the extension module 208 at a location remote of the access point and preferably proximate to a respective remote terminal that is within a poor coverage region or is outside of the coverage area 110 but it is desired to communicate with the access point. The wireline extension 204 couples to a power amplifier 602 that amplifies the signal to account for attenuation over the wireline extension 204 for transmission over the wireless communication medium. The power amplifier 602 is coupled to a filter 604, which is coupled to the antenna 210. The filter 604 may be a bandpass filter that passes the desired wireless frequencies and blocks other signaling that might be present on the wireline extension. It is noted that the filter 604 is not required; however, it is preferred if there is other signaling present on the wireline extension (e.g., the wireline extension 204 is a cable plant also carrying traditional television or internet signaling). In preferred embodiments, the wireline extension 204 is the cable plant of the home or business and the extension module 208 is a simple module that connects directly to an unused cable connection or jack. The extension module 202 simply functions to amplify the signal and transmit it wirelessly via the antenna 210. It is noted that the signal has already been modulated and upconverted for the wireless transmission at the transmitter portion 302 of the access point.

FIG. 6B is a block diagram of one embodiment of an extension module coupled via wireline to the splitter module 202 of FIG. 5 that transmits and receives wireless communications to and from one or more remote terminals of the network of FIG. 2. The wireline extension 204 couples to the range extension module 212 at combiner 606 which couples the signaling on the wireline extension to the power amplifier 602. The signal is amplified and coupled to the optional filter 604 via combiner 608. If present, the filter 604 passes the desired signaling while the blocking other signaling present in the wireline extension. The filtered transmit output is coupled to the antenna 214 for transmission to nearby remote terminals, e.g., RT 106D and 106E. In this embodiment, since the remote terminals 106D and 106E are out of range for communications back to the access point via the wireless communication medium, the antenna 214 also receives the uplink signaling. This signaling is filtered at filter 604, then coupled to a low noise amplifier 610 and coupled to the wireline extension 204 via combiner 606. The combiners 606 and 608 function to couple the signaling transmitted and received to and from the wireline extension 204 and the antenna 214. The low noise amplifier 610 is a standard component to amplify the received signal in order to account for any signal attenuation from the range extension module 212 back to the access point 102 via the wireline extension 204.

Again, in preferred embodiments, the wireline extension is an existing cable plant of the home or business. Thus, the range extension module 212 is coupled to the wireline extension 204 at a cable connection. The range extension module 212 differs from the extension module 208 of FIG. 6A in that it includes both transmit and receive functionality. However, it is noted that depending on the quality of service of the uplink communication, the range extension module 212 may be implemented in place of the extension module 208. For example, if RT 106C were transmitting high data rate video signals (e.g., video conferencing signals) back to the access point 102, wireless transmission from the remote terminal 106C back to the access point may also be unreliable since the access point would be in a poor coverage region relative to RT 106C. However, the extension module 212 provides a remote location closer to RT 106C that could reliably receive the signaling over the wireless communication medium from RT 106C and then relay it via the wireline extension 204 to the access point 102. The access point 102 would then receive the signal as if it were received at antenna 104. Referring to FIGS. 2-6B, a link budget is illustrated in an embodiment in which the wireline extension 204 comprises an existing cable plant. Thus, the TX output of the wireless access point communication terminal is coupled to the antenna 104 and also to the cable plant of the home or business. As illustrated in several link budgets of Table 1 below, the cable losses vary depending on the type of cable used. For example, RG-59 and RG- 6 are examples of well known coaxial cables commonly used in homes and businesses. Without the gain at the extension modules 208 and 212, the combination of cable and splitter losses plus the final free space wireless link from the extension module 208 to the RT can be larger than the direct wireless propagation loss from the antenna 104 to the RT. Thus, a low power amplifier (e.g., 40 dB) is provided at each extension module 208 and 212. However, it is noted that the value of the amplification may vary depending on the link budget and receiver requirements. Accordingly, the RTs can reliably receive the signaling at the power levels received. Additionally, it is noted that the extension modules 208 and 212 provide improved reception at the remote terminal without having to increase the AP transmit power level or decrease the data rate of the signaling.

TABLE 1

Referring next to FIG. 7, a diagram is shown of a hybrid wireless/ wired local area network 700 according to another embodiment of the invention including wireless remote terminals 106 and one or more wired remote terminals 702 that communicate with the access point via wireline. Thus, the downlink signaling from the access point 102 to RTs 106 is transmitted via the wireless communication medium and transmitted via the wireline to wired RTs 702. In this embodiment, the splitter module 202 couples the TX output to the antenna 104 and to the wireline extension 204. The wireline extension 204 may include one or more passive splitters, e.g., passive splitters 206. The remote terminals 702 connect via a wireline connection 704 to the wireline extension 204. Thus, RTs 702 received wired downlink signals from the AP 102 and transmit wired uplink signals to the AP 102 via the wireline extension 204. In preferred embodiments where the wireline extension 204 comprises the existing cable plant, the wired remote terminals 702 are simply connected to unused cable jacks. Advantageously, in this embodiment, power amplifiers are generally not required to boost the signals to the wired remote terminals 702 since the signal is not transmitted over a wireless hop to the remote terminals.

FIG. 8 illustrates a block diagram of one embodiment of a simple extension module coupling the wireline extension 204 to the wired remote terminal 702 of FIG. 7. In this embodiment, since no amplification is required, the wireline extension 204 is coupled to a combiner 802 that relays the downlink signals to the RX input of the wired remote terminal 702 and relays uplink signals from the TX output of the wired remote terminal 702 to the wireline extension 204.

According to this embodiment, the network 700 provides both wired and wireless networking occurring substantially simultaneously on the same RF channel designed for wireless transmission. The wired RTs 702 participate in the network 700 during their scheduled time-slots just as if they were wireless with all signals received within the expected time window including the guard time interval. Propagation time through the extension wireline 204 as compared to the wireless network would be inconsequential owing to the TDD / OFDM system structure involved.

Table 2 below illustrates a simple link budget for the wired portion of the network 700. In one embodiment, using various known coaxial cable as the wireline extension 204, there is sufficient link budget for full throughput via 200 feet of cable.

TABLE 2

The hybrid network 700 provides many advantages including that remote terminals may be connected to the network via wireline or via wireless connections. Additionally, all users in the network 700, whether wireless or wired participate in the same homogeneous network thereby simplifying the merging of what would typically be two separate networks, i.e., a separate wireless network and a separate wired network. In a residential application, a user who is hesitant to try wireless networking may ease their way into it, by using as much or as little of the wireless ability as desired while the network advantageously uses the same hardware for both wired and wireless connectivity. In unusual situations or extremely dense- deployment situations where wireless networking becomes problematic, the same hardware could be used to do networking over a pre-existing home/ business cable plant. Furthermore, since the network 700 was originally based upon wireless communication through a multipath medium, the network is built to deal with greater coaxial losses than standard coaxial transmission systems.

In preferred embodiments, the wired portion of the network 700 operates in the same frequency channels that are allocated for wireless use, e.g., in the same 5 GHz channels of the IEEE 802.11a standard. Similar to the hybrid network 200, the downlink signaling from the AP 102 is "simulcast" from the AP 102 over the wireless communication medium and over the wireline extension 204 at the same time. Taking this approach permits the same hardware to be used for both wireless and wired situations. Referring next to FIG. 9, a block diagram is shown of a variation of the hybrid wireless/ wired network of FIG. 7 in which one or more remote terminals coupled to the access point via the wireline extension also simultaneously communicate with the access point 102 wirelessly providing a hot-swappable remote terminal that may communicate wirelessly and/ or wired with the access point.

In this embodiment, the hybrid network 900 includes remote terminals 106 that communicate wirelessly with the AP 102, wired terminals 702 that communicate via a wired connection to the AP 102 and a swappable remote terminal 902 that can interchangeably communicate using wired and/ or wireless communications with the AP 102. Thus, RT 902 is similar to RT 106; however, it includes a splitter module 1002 illustrated in FIG. 10 that is similar to the splitter module 202 coupled to the AP 102. Thus, the splitter module 1002 splits the RT TX output to antenna 108 and to the wireline extension 204 via the wired connection 704. Likewise, the splitter module 1002 combines the signaling received from the antenna 108 and the wireline extension 204 to make the RX input of the swappable RT 902. Advantageously, the RT 902 can operate using both wired and wireless communications, only wired communications, or only wireless communications. This is because the receiver portion 304 (particularly, an OFDM receiver) is especially adapted handle multiple reflections of the same signal due to the multipath wireless channel. Thus, from the point of view of the receiver portion 304, the wired and wireless signals appears as different reflections of the originally transmitted signaling. Therefore, it does not matter whether the signaling was transmitted and received over the wired and/ or wireless mediums as long as both wired and wireless communications occur during the allotted time slots and all signals are received within the time period including the guard time interval. Thus, in one embodiment, the RT 902 may be disconnected or connected in mid-communication from one of the wireless or wired connections. If one of the connections is disconnected, the receiver portion 304 simply receives less reflections of the signaling. If one of the connections is added, the receiver portion 304 simply receives additional reflections, which it is well capable of handling.

Furthermore, in preferred embodiments in which communications are time division duplex (TDD), a user could in many cases connect or disconnect themselves from a wired connection without interruption in service. Thus, the user may switch between wired and wireless communications without losing synchronization with the access point 102 or having to re-associate with the access point 102.

FIG. 10 illustrates the splitter module 1002 coupled to the transceiver of the hot swappable RT 902 that allows wireless and/ or wired communications with the access point. The downlink signaling from the AP 102 to the RT 902 is received via the wireline path (e.g., through the wireline extension 204 and the wired connection 704) and received via the RX antenna 108A and wire 1006 at the combiner 1004. The combiner 1004 outputs the TX output of the AP 102 as the RX input of the RT 902.

The modulated and upconverted TX output of the RT 902 is split at coupler 1008 to the TX antenna 108B of the RT 902, e.g., via wire 1010. The coupler 1008 also outputs the TX output to power amplifier 1012 to amplify the uplink signaling for transmission over the wireline extension 204. The amplified signal is coupled to the wireline extension 204 via the combiner 1004 and the wired connection 704. As illustrated, the splitter module 1002 is similar to the splitter module 202 at the AP 102. That is, it allows its transmit output to be simultaneously transmitted via both wireless and wired mediums. It also allows for inputs to be received via both wireless and wired mediums.

In one embodiment, the RT 902 is intended to operate wirelessly with the AP 102. However, as the user moves the RT 902 into an area of poor wireless coverage or outside of the wireless coverage area, the user may also connect the swappable RT 902 to the wireline extension to provide reliable communication even in area of poor wireless coverage. For example, the swappable RT 902 may be attached with the appropriate and well known connectors to an unused cable jack of the home or business.

Referring next to FIG. 11, a block diagram is shown of an access point of a hybrid wireless/ wired network in which wireless communications and wired communications are transmitted from and received at the access point 102 at different frequencies. In this embodiment, the baseband processing portion 332 of the communication terminal 300 of FIG. 3 is coupled to a splitter 1104 which splits the signaling into two separate RF portions 1106 and 1108 (also referred to as RF transceivers). RF portion 1106 includes the functionality to upconvert the downlink signaling to a first frequency intended for the wireless communication medium (e.g., 5 GHz) and downconvert uplink signaling received at antenna 104 to baseband. RF portion 1108 includes the functionality to upconvert the downlink signaling to a second frequency that is more optimal for transmission on the wireline extension 204 (e.g., 1-1.5 GHz) and downconvert uplink signaling received over the wireline extension 204 to baseband. The transmit output is hopped or switched between RF portion

1106 and RF portion 1108 depending on the destination of the given signal according to time slot allocation. Control signals 1110 are provided to ensure that while one RF portion is transmitting, the other is not, and vice versa. Even though two different radio transceivers (i.e., RF portions 1106 and 1108) are being used, the baseband signal processing and MAC hardware/ firmware support multiple user time slots per MAC frame, hopping between the two RF portions 1106 and 1108 as the users' time slot characteristics require. This permits wireless and wired network services to be managed by one single MAC entity, and thereby provides complete connectivity and uniformity between all users being networked, whether wireless or wired.

Advantageously, by transmitting the signaling over the wireline extension 204 at a frequency more suitable to wireline transmission, considerably less cable losses will occur over wireline extension which will extend the range of the wired portion of the hybrid network 1102. For example, in embodiments where the wireline extension is the cable plant, signaling loss is cut in approximately half moving from 5 GHz to about 1 GHz.

Additionally, the use of an alternative frequency band (e.g., 1.0 - 1.5 GHz) over the wireline extension in addition to the 5.0 GHz which could also be transmitted over the wireline extension with the appropriate splitter module 202 at the output the RF portion 1106 could provide more bandwidth for many more users is dense-deployment situations than available if restricted only to the 5 GHz wireless band alone or to existing cable channel assignments. FIG. 12 is a diagram of a hybrid wireless/ wired local area network according to yet another embodiment of the invention in which a wireless access point designed to communicate wirelessly with a plurality of remote terminals is coupled to and communicates with its remote terminals via wireline. In this embodiment of the hybrid network 1200, the transmit output of the AP 102 is not transmitted over the wireless communication medium. The transmit output (e.g., TX output of FIG. 3) is coupled via wireline connections directly to the wired RTs 702. For example, the AP output is coupled to a passive splitter 206 which outputs the signal to the wireline extension 204 or directly to the wired RTs 702 via wired connection 704.

Such network 1200 resembles a traditional wired network; however, in contrast to known wired networks, the access point 102 is configured to transmit its signaling via a multipath wireless communication medium. Thus, such an access point 102 has the ability to communicate wirelessly with one or more remote terminals. In one embodiment, the AP

102 includes an OFDM communication terminal 300 such as illustrated in FIG. 3, e.g., OFDM according to IEEE 802.11a. Thus, the medium access control and physical layer of the AP 102 are configured for wireless transmission, even though it is ultimately used in an all- wired implementation. Such an AP 102 would be significantly more complex than that which would be required for traditional wired networking. Especially since the wired networking access point does not have to deal with severe multipath reflection present in the wireless channel. For example, a traditional wired access point would employ a much less complex single carrier transmission scheme and be able to transmit using higher data rates with higher order constellations (e.g., 256-QAM), since the signaling is to be transmitted over wireline rather than a multipath wireless link. A multicarrier transmission scheme over wireline would introduce unneeded complexity in the transmitter accounting for negligible reflections through the wireline. Even if a multicarrier scheme were to be used for wireline transmissions, very few carriers may be needed. For example, multicarrier schemes suitable for wireless transmission may include at least 10 subcarriers (e.g., 48 data bearing subcarriers in OFDM in IEEE 802.11a). Anything more than 2-8 subcarriers in a wireline transmission would not further reduce any reflections and would add considerable complexity to the system.

While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.

Claims

What is claimed is: 1. A hybrid wireless/ wired network comprising: a communication terminal for communicating wirelessly with each of a plurality of remote communication terminals of a wireless network, the communication terminal functioning as an access point of the wireless network; a first antenna coupled to an output of the communication terminal for wirelessly transmitting signaling to the plurality of remote communication terminals; and a wireline extension coupled to the output of the communication terminal for transmitting the signaling via the wireline extension a distance to a remote location.

2. The network of claim 1 further comprising a splitter coupled to the output of the communication terminal, the splitter splitting the signaling to both the first antenna and the wireline extension.

3. The network of claim 1 further comprising: an extension module coupled to the wireline extension at the remote location and having a second antenna for wirelessly transmitting the signaling to one or more of the plurality of remote communication terminals.

4. The network of claim 3 wherein a respective remote communication terminal is in a poor coverage region within a coverage area of the signaling such that the respective remote communication terminal is not reliably receiving the signaling wirelessly transmitted from the first antenna at a given transmit power level and a given data rate; wherein the extension module wirelessly transmits the signaling to the respective remote communication terminal in order to fill in the poor coverage region without having to increase the given transmit power level or decrease the given data rate.

5. The network of claim 3 wherein the extension module wirelessly transmits the signaling to a respective remote communication terminal that is not within a coverage area of the signaling in order to extend the range of the coverage area of the signaling.

6. The network of claim 3 wherein the signaling from the communication terminal to the plurality of remote communication terminals comprises high quality of service signaling such that a respective remote communication terminal is not within a coverage area for high quality of service signaling from the communication terminal at a given transmit power level at a given data rate; and wherein the remote communication terminal is able to reliably receive the high quality of service signaling from the extension module without requiring that the communication terminal increase the given transmit power level or decrease the given data rate.

7. The network of claim 3 wherein the extension module further comprises an amplifier coupling the wireline extension to the second antenna for amplifying the signaling prior to being wirelessly transmitted.

8. The network of claim 1 wherein a respective remote communication terminal is coupled to the wireline extension at the remote location via a wired connection.

9. The network of claim 8 wherein the respective remote communication terminal receives the signaling via the wired connection and further includes a second antenna for receiving the signaling wirelessly transmitted from the first antenna.

10. The network of claim 9 wherein the respective remote communication terminal can switch between receiving the signaling via the wired connection and receiving the signaling wirelessly transmitted from the first antenna.

11. The network of claim 1 wherein the communication terminal comprises: a baseband processing portion for processing data to be transmitted to the plurality of remote communication terminals; and a radio frequency portion coupled to the baseband processing portion and providing the output that is to be transmitted to the plurality of remote communication terminals.

12. The network of claim 11 wherein the radio frequency portion comprises a first radio frequency portion coupling the output to the first antenna and a second radio frequency portion coupling the output to the wireline extension; the first radio frequency portion converting the signaling to a first radio frequency for wireless transmission by the first antenna to the plurality of remote communication terminals; and the second radio frequency portion converting the signaling to a second radio frequency for transmission over the wireline extension.

13. The network of claim 1 wherein the wireline extension comprises a cable plant.

14. The network of claim 1 wherein the communication terminal and each of the plurality of remote communication terminals comprise orthogonal frequency division multiplexed (OFDM) communication terminals, wherein the signaling comprises OFDM signaling.

15. The network of claim 1 further comprising an extension module coupled to the wireline extension at the remote location, the extension module for transmitting the signaling to one or more of the plurality of remote communication terminals; the one or more of the plurality of the remote communication terminals transmitting return signaling to the access point via the wireless communication medium.

16. The network of claim 1 further comprising an extension module coupled to the wireline extension at the remote location, the extension module for transmitting the signaling to one or more of the plurality of remote communication terminals; the one or more of the plurality of the remote communication terminals transmitting return signaling to the access point via the extension module and the wireline extension.

17. A method for use in a wireless network comprising: transmitting signaling from a communication terminal to a plurality of remote communication terminals via a wireless communication medium, the wireless communication medium providing a plurality of multipaths, wherein one or more of the plurality of remote communication terminals receives multiple reflections of the signaling within a nominal window of time, the communication terminal configured to function as an access point of the wireless network; and transmitting the signaling from the communication terminal to a remote location a distance from the communication terminal via a wireline extension.

18. The method of claim 17 further comprising: transmitting the signaling from the remote location to a respective remote communication terminal such that the signaling transmitted from the remote location arrives at the respective remote communication terminal within the nominal window of time, wherein the signaling transmitted from the remote location appears as one or more reflections of the signaling transmitted from the communication terminal via the wireless communication medium.

19. The method of claim 18 wherein the transmitting the signaling from the remote location to the respective remote communication terminal comprises: wirelessly transmitting the signaling from the remote location to a respective remote communication terminal.

20. The method of claim 18 wherein the respective remote communication terminal is coupled to the wireline extension at the remote location via a wired connection, wherein the transmitting the signaling from the remote location to the respective remote communication terminal comprises: transmitting the signaling from the remote location to a respective remote communication terminal via the wired connection.

21. The method of claim 20 wherein the respective remote communication terminal receives the signaling via the wired connection and receives the signaling wirelessly transmitted over the wireless communication medium, the respective remote communication terminal being able to switch between receiving the signaling from the remote location and receiving the signaling over the wireless communication medium.

22. The method of claim 17 wherein a respective remote communication terminal within the wireless network is within a poor coverage region of a coverage area of the signaling with respect to a given data rate and a given transmit power level of the signaling from the communication terminal to the respective remote communication terminal such that the respective remote communication terminal is unable to reliabl receive the signaling at the given data rate and the given transmit power level, the method further comprising: transmitting the signaling from the remote location to the respective remote communication terminal, wherein the respective remote terminal is able to accurately receive the signaling transmitted from the remote location, wherein reception within the poor coverage region is improved without having to increase the given transmit power level or decrease the given data rate.

23. The method of claim 17 wherein the remote location is a located outside of a coverage area for the signaling transmitted at a given transmit power level and a given data rate from the communication termina over the wireless communication medium, the method further comprising: transmitting the signaling to one or more additional remote communication terminals from the remote location; and the one or more additional remote communication terminals n able to accurately receive the signaling transmitted from the communication terminal over the wireless communication medium, receive the signaling transmitted from the remote location without having to increase the given transmit power level or decrease the given data rate.

24. The method of claim 17 wherein the transmitting the signaling from the communication terminal to the plurality of remote communication terminals comprises: transmitting the signaling from the communication terminal to the plurality of remote communication terminals via the wireless communication medium at a first frequency; and wherein the transmitting the signaling from the communication terminal to the remote location comprises: transmitting the signaling from the communication terminal to the remote location via the wireline extension at a second frequency.

25. The method of claim 17 wherein the respective remote communication terminal transmits uplink signaling to the communication terminal via the wireless communication medium, the uplink signaling at a lower data rate than that of the signaling from the communication terminal to the remote communication terminal.

26. The method of claim 17 further comprising transmitting the signaling from the remote location to a respective remote communication terminal; wherein the respective remote communication terminal transmits uplink signaling to the communication terminal via the wireless communication medium, the uplink signaling at a lower data rate than that of the signaling transmitted from the communication terminal over the wireless communication medium.

27. The method of claim 17 further comprising transmitting the signaling from the remote location to a respective remote communication terminal; wherein the respective remote communication terminal transmits uplink signaling to the communication terminal via the remote location and the wireline extension.

28. The method of claim 17 wherein transmitting the signaling from the communication terminal to the remote location comprises transmitting the signaling from the communication terminal to the remote location the distance from the communication terminal via a cable plant.

29. The method of claim 17 wherein the transmitting signaling steps comprising transmitting orthogonal frequency division multiplexed

(OFDM) signaling.

30. A hybrid wireless/ wired network comprising: a communication terminal configured to communicate wirelessly with each of a plurality of remote communication terminals of a wireless network over a wireless communication medium, the communication terminal configured to function as an access point of the wireless network; the plurality of remote communication terminals coupled to the communication terminal via wireline; and wherein the communication terminal transmits signaling formatted for wireless transmission to the plurality of remote communication terminals via the wireline.