WO2003096599A1 - Diversitätsverfahren und vorrichtung - Google Patents
Diversitätsverfahren und vorrichtung Download PDFInfo
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- WO2003096599A1 WO2003096599A1 PCT/EP2003/004759 EP0304759W WO03096599A1 WO 2003096599 A1 WO2003096599 A1 WO 2003096599A1 EP 0304759 W EP0304759 W EP 0304759W WO 03096599 A1 WO03096599 A1 WO 03096599A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
- H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
- H04B7/0667—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of delayed versions of same signal
- H04B7/0669—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of delayed versions of same signal using different channel coding between antennas
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0045—Arrangements at the receiver end
- H04L1/0047—Decoding adapted to other signal detection operation
- H04L1/0048—Decoding adapted to other signal detection operation in conjunction with detection of multiuser or interfering signals, e.g. iteration between CDMA or MIMO detector and FEC decoder
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0045—Arrangements at the receiver end
- H04L1/0054—Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0056—Systems characterized by the type of code used
- H04L1/0071—Use of interleaving
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
- H04L1/06—Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity
- H04L1/0618—Space-time coding
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
- H04L1/06—Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity
- H04L1/0618—Space-time coding
- H04L1/0625—Transmitter arrangements
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
- H04L1/06—Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity
- H04L1/0618—Space-time coding
- H04L1/0631—Receiver arrangements
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
- H04L1/06—Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity
- H04L1/0618—Space-time coding
- H04L1/0637—Properties of the code
- H04L1/065—Properties of the code by means of convolutional encoding
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/0204—Channel estimation of multiple channels
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/024—Channel estimation channel estimation algorithms
- H04L25/0242—Channel estimation channel estimation algorithms using matrix methods
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L2025/03592—Adaptation methods
- H04L2025/03598—Algorithms
- H04L2025/03605—Block algorithms
Definitions
- the present invention relates to digital transmission technology and in particular to concepts for a message transmission over channels that have a strong fading, such as. B. radio channels.
- WO 00/367783 discloses an apparatus and a method for transmitting information and an apparatus and a method for receiving information.
- the device for sending information comprises an information source, a redundancy-adding encoder with a code rate less than 1/2, a splitter for dividing the output of the encoder into two separate data streams, a data stream being transmitted over a first channel while the other data stream is transmitted over a second channel.
- the redundancy-adding encoder enables forward error correction, which is used in a receiver-side decoder, in order to ensure good reception quality.
- the first and the second channel differ in that they are spatially different, and in that a time diversity function is also built in, in that an information transmitted via the first channel at a later time again via the other channel is transmitted.
- receivers On the receiver side there are two different receivers for receiving the signal transmitted over the first channel on the one hand and for receiving the signal transmitted over the other channel on the other.
- the receiver output signals are combined by means of a combiner and fed to a decoder, which is constructed, for example, as a Viterbi decoder and whose output output values are fed into a Reed-Solomon decoder.
- the satellites are designed such that they transmit in different frequency bands. It is thus easily possible to distinguish the signal from one satellite from the signal from the other satellite, since the satellite reception signals are in different frequency bands and can be received in a frequency-selective manner.
- a disadvantage of this concept is the fact that two complete frequency bands are required, namely a first frequency band on which the first satellite transmits and a second frequency band on which the second satellite transmits.
- the bandwidth of a transmission channel is a scarce commodity, so that often very little bandwidth is available for an application or that the bandwidth required by an application has to be paid for expensively. This significantly increases the cost of a system. Particularly in the case of radio applications, in which the development and installation effort of the transmitters and the satellites has to be transferred to the receiving devices, this leads to an increase in the cost of the receiving devices. In the highly competitive market of radio receivers, however, small or medium price differences can result in one system becoming established on the market, while another system is unsuccessful and disappears from the market.
- the object of the present invention is to create a cheaper transmission / reception concept. This object is achieved by a transmitting device according to patent claim 1, a method for transmitting according to patent claim 11, a receiving device according to patent claim 12 or a method for receiving according to patent claim 21. '
- the present invention is based on the finding that a transmitter device with a redundancy-adding encoder in order to achieve forward error correction is coupled with two transmitters which have spatially different positions in order to achieve space diversity, further preferably using an interleaver there is also a time diversity function.
- both transmitters transmit in the same frequency band using the same carrier frequency.
- a space diversity with forward error correction (by the redundancy-adding encoder) and preferably also a time diversity is achieved by means of respective interleavers in the two transmission devices, while only one frequency band is required, in that compared to the known transmission / Reception concept only half the bandwidth is required, so that only half the bandwidth costs are incurred.
- the receiver concept according to the invention is therefore oriented in such a way that it synchronously scans the reception signal applied to a reception antenna for the first transmitter in order to obtain a first reception signal, and also synchronously siert on the second transmitter to receive a second receive signal. Both reception signals are disturbed by interference from the other transmitter. To reduce or eliminate this interference, the two received signals are decoded in order to recover received code units that the redundancy-adding encoder has generated in the transmitter.
- Interference signals in the receiver are calculated from these code units and - in an iterative loop with one or more iteration steps - subtracted from the two received signals in order to achieve interference reduction.
- the interference-reduced reception signals that is to say the improved reception signals, are then fed back to the decoder in order to recover the information word on which the code units are based on the basis of the interference-reduced reception signals.
- a controller is provided which on the one hand controls the iteration and on the other hand determines whether a termination criterion of the iteration has been determined.
- a redundancy-adding encoder with a code rate R c of 1/4 is used, which generates four code units from one information unit. These code units are then divided into two sub-groups of code units, so that the first transmitter receives two code units and the second transmitter also receives two code units.
- Respective interleavers in the two transmission branches provide a time diversity function, which is particularly useful in the case of burst errors, such as. B. Deep Fades, is an advantage.
- Each transmitter also includes a QPSK mapper to perform QPSK modulation.
- two code units are grouped at the output of an interleaver, after which a QPSK symbol is assigned to this 2 code unit group, which is then converted to a carrier frequency and transmitted by the transmitter.
- a demap is located in the receiver under the usual receiver front end, which includes the antenna and a downconversion device. provided to recover the two code units from a received QPSK symbol.
- the demapper in a preferred embodiment of the present invention is designed as a soft demapper such that it does not make a hard decision, but rather provides probabilities that a code unit is a 0 or a 1.
- the code units which are available as probabilities, are again fed to a de-interleaver, which reverses the code unit interleaving in the transmitter.
- the “de-interleaved” code unit probabilities are then supplied to a soft-in-soft-out decoder, which is preferably designed as a BCJR-SISO decoder.
- the SISO decoder is supplied with the probabilities for code units from both reception branches, specifically as pre-decoding probabilities.
- the SISO decoder supplies post-decoding probabilities for the individual coding units, which are used to estimate the interference signals.
- the post-decoding probabilities are again interleaved as in the transmitter and estimation devices are supplied in order to "softly" estimate the transmitted QPSK symbols from the code unit probabilities.
- the estimated QPSK symbols are then loaded in the receiver with a transmission channel characteristic which is obtained by conventional channel estimation methods in order to obtain interference signals which are finally subtracted from the received signals "crosswise".
- the interference signal which is based on the second received signal has been calculated, subtracted from the first received signal, while the interference signal calculated on the basis of the first received signal is subtracted from the second received signal, so that improved first and second received signals are obtained which, in turn, are processed like the “original first and second received signals” in order to again calculate post-decoding probabilities with which a further iteration loop can be entered.
- a set of extrinsic decoding probabilities is calculated from the post-decoding probabilities at the output of the SISO decoder, which, after corresponding interleaving processing, are also supplied to the demapper in a branch as side information in order to provide a rotation variant Distortion in the samples due to the interference reduction to be taken into account.
- the receiver concept according to the invention has the advantage that it makes it possible to use a transmitter device in which both transmitters operate in the same frequency band, so that, compared to known concepts, only half the bandwidth of the transmission channel is required.
- the iterative interference reduction using a channel decoder which is preferably a SISO decoder and in particular a BCJR decoder, reduces the interference at the receiving antenna, which would normally prohibit a transmission concept with two transmitters transmitting at identical frequencies. Since components in the receiver can be used several times, namely for each iteration loop, the effort in the receiver is limited and cost-effective and is of the order of magnitude lower than a transmission / reception concept with doubled bandwidth.
- Another advantage of the concept according to the invention is the rapid convergence. Significant interference reductions are obtained after the first iteration step. After only between four and six iteration steps Only a minimal change in the decoded code units is found from iteration to iteration, so that a rapid convergence is ensured.
- Another advantage of the present invention is that all processing can be carried out in the baseband, so that no complex and expensive digital circuits or even analog circuits are required to carry out the interference reduction, for example in the IF band or in the HF band, although this is basically also possible.
- Another advantage of the present invention is that generally known modules can be used, namely FEC encoders and QPSK mappers in the transmitter and QPSK demappers, estimators and trellis decoders in the receiver that match the FEC encoder in the transmitter.
- FIG. 1 shows a block diagram of a transmitting device according to the invention
- FIG. 2 shows a preferred exemplary embodiment of a transmission device
- 3 shows a baseband model of a transmission that is continuous over time
- FIG. 4 shows a schematic block diagram to illustrate a time-discrete transmission
- Fig. 5 shows a block diagram of a receiving device according to the invention
- 6 shows a preferred exemplary embodiment of a receiving device with a soft demapper
- Figure 10 shows the probability density function of received samples for the demapping function of Figure 11.
- Fig. 1 shows a schematic representation of a transmitter according to the invention.
- An information source 10 provides an information word u with a plurality of information units. This information word is fed into a redundancy-adding encoder 12, which has a code rate less than or equal to 1/2.
- the FEC encoder 12 generates a plurality of code units from the information word, the encoder 12 also being effective in dividing the plurality of code units into two subgroups of code units.
- a first subset of code units is connected to a first output line 14a of the co- This is fed to a first transmitter 16a, while the second subset of code units on a second output line 14b of the encoder is made available to a second transmitter 16b.
- the first transmitter 16a is connected to a first transmission antenna 18a to radiate a first transmission signal
- the second transmitter 16b is connected to a second transmission antenna 18b to radiate a second transmission signal.
- the first and the second transmitter are arranged at different spatial positions. According to the invention, however, both transmitters transmit in the same frequency band, so that the first transmission signal and the second transmission signal superpose themselves in free space.
- the two transmitters are preferably satellites arranged at different geostationary positions, while a receiver z. B. is a radio receiving device in a moving vehicle.
- FIG. 2 shows, inter alia, a preferred embodiment for the transmitter according to the invention from FIG. 1.
- an encoder with a code rate R c of 1/4 as the encoder 12, such that a plurality of one information word u a plurality of code units is generated by information units, which is greater than or equal to four times the plurality of information units.
- the plurality of code units represent a code word c, which is divided into two subgroups or subcode words c (1> and c ⁇ 2) .
- the information word is preferably a binary information word which is channel-coded by the encoder 12, which is designed as a convolutional encoder and has a given memory v and has a rate of R c equal to 1/4.
- This encoder stops after the input of K information bits, that is to say after the input of the plurality of information units in the 0 state, which in other words means that v "trailing" completion bits are inserted.
- the encoder therefore generates four code bits c n for each input bit u k , which are divided in the parallel / serial converters 13a, 13b into the subgroups or subcode words of length N / 2 for a first transmitter 16a and the second transmitter 16b , Each transmitter comprises an interleaver 20a or 20b.
- interleavers are preferably designed as s-random interleavers to carry out a permutation, as described in S. Dolinar and D. Divsaler, "Weight Distributions for Turbo Codes Using Random and Nonrandom Permutations", JPL-TDA Progress Report 42-122, pp. 56-65, 1995.
- the two bit interleavers 20a, 20b permute the vectors c (1) and c ⁇ 2) .
- a gray mapping is used as the mapping rule, in which the following conventions apply:
- Gray mapping is advantageous in that one bit of a pair of permuted code bits stands for the imaginary part and the other bit stands for the real part.
- some known transmitter front end is provided, which, for. B. performs a complex modulation and upmixing to a carrier frequency with the QPSK symbols.
- the simplest way to obtain a space diversity for the transmitters is to have an encoder with a rate R c of 1/2 in order to duplicate the code words, which leads to the fact that the first subset of Code units and the second subset of code units are identical, so that a total code rate of 1/4 is also obtained.
- the same code bits are therefore transmitted twice, the vector c (2) in the satellite being a simply permuted version of the corresponding sub-code word for the first satellite due to the interleaver in the two branches.
- a real code with a code rate 1/4 instead of a simple repetition code, especially since a real code with a code rate of 1/4 provides higher performance efficiency than a simple repetition code since the generation additional code bits instead of simply duplicating them leads to higher code diversity.
- the memory of the convolutional encoder v is 6.
- the total rate is somewhat lower due to the additional symbols due to the completion of the convolutional encoder.
- four code units are generated from one information unit, with two code units each then being grouped into two QPSK symbols (from transmitter 1 and from transmitter 2), so that again, in terms of numbers, two QPSK symbols are generated from one information unit.
- the two QPSK symbols are transmitted by the two transmitters on the same frequency, one transmission process is carried out per information unit at a time and at the same frequency (but of course using both transmitters), so that, according to the convention, an overall code rate of 1 or slightly less than 1, as stated above.
- the QPSK-mapped vector x (1) or x (2) of the two transmitters 16a, 16b is pulse-amplitude modulated.
- the transmission filter is a square root Nyquist filter for a symbol duration Ts with a real-valued impulse response g (t).
- the fraction of the propagation delay between the transmitter and the receiver is Ti e [- 0.5 x T s ; 0.5 x T s ]. FER It is now assumed that the integer part of the propagation delay can be accurately estimated through appropriate measures.
- the transmission signal typically experiences a frequency-flat rice fading with a slowly varying fading coefficient a (1) (t).
- the satellite 2 uses the same transmission filter G (f) 30b, but with a fraction of its propagation delay to the receiver T 2 e [-0.5 x T s ; 0.5 x T s ].
- a second slow and frequency-flat rice fading process is also used for the second satellite, which is statistically independent of the first fading process.
- the signals of both satellites are combined on the receiving antenna of the receiving device according to the invention, as represented by a summer 36 in FIG. 3.
- the two filters 30a, 30b thus represent the pulse formation in the transmitter, while the two time delay elements 32a, 32b model the transit time of the signal from the first transmitter to the receiver or the transit time of the signal from the second transmitter to the receiver.
- the channel fading is modeled by the multipliers 34a, 34b, while the receiver begins, as it were, from the summer 36, since the summer 36 models the superposition of the two transmission signals on the receiving antenna of the receiving device according to the invention.
- the received signal y (t) at the output of the summer 36 can be represented in the same way as follows:
- y (t) a (l, (t) -Xx ( "[k] .g (t-kT s -T 1 ) + a (2) (t) -Xx (2) [k] -g (t -kT s -T 2 ) (1)
- the receiving antenna In addition to the summation performed by the receiving antenna, it also adds white Gaussian noise (WGN) with a one-sided spectral power density N 0 .
- WGN white Gaussian noise
- the received signal is then filtered with a receiver pulse shaping filter 38 with a transfer function G * (f), so that the output signal at this receive filter 38 is equally defined as follows:
- ⁇ gg (t) is the autocorrelation function of g (t).
- n (t) the superimposition of which on the received signal is symbolically represented by an adder 35, represents the filtered noise n (t), the power of which is given as follows:
- the receiver now tries to synchronize itself in two branches with a corresponding satellite, so that the output signal of the receiver filter 36a is sampled at times ix T s + Ti + T ⁇ in order to provide a time-discrete signal for the satellite 1 to obtain.
- sampling is carried out at times ix T s + T 2 + ⁇ 2 in order to obtain a time-discrete signal y ( s ⁇ c for the satellite 2.
- ⁇ i, ⁇ 2 represent the error of the symbol clock recovery for the two satellites, ie the synchronization of a first sampler 40a and a second sampler 40b.
- Ti, x 2 are much smaller than T s , ie the symbol duration, and therefore the two discrete-time samples for each symbol interval are as follows Are defined:
- the time-continuous transmission model is replaced by a time-discrete transmission model, as shown in FIG. 4.
- the transmission delays Ti, T 2 (32a, 32b) of FIG. 3 are modeled together with possible synchronization errors of the samplers 40a, 40b in four filters 42a-42d shown in FIG. 4.
- the QPSK symbols in the vector x (1) are multiplied by the respective elements of the vector a (1) , which corresponds to the slow and frequency-flat rice fading process.
- the elements of x (2> are multiplied element by element by the fading coefficients in a (2) .
- the resulting vectors y (1) and y ⁇ 2) are then filtered with the four filters 42a-42d, as shown in FIG. 4 is shown.
- the respective impulse responses of these filters are as follows:
- the filters H 12 ⁇ 1) (z) and H (1 ⁇ 2) (z) represent the interference of the signal of the satellite in the samples which have been sampled synchronously on the satellite 1 and vice versa. These filters are mainly by the difference Ti - T 2 of the propagation delay from both satellites to the receiving device is determined.
- the output signals of these filters are the vectors y ⁇ ',. and y ⁇ t of the interference samples.
- the output signals of these filters thus represent the interference signals that occur during the actual transmission and, as will be explained later, are estimated by the receiving device according to the invention in order to carry out interference reduction in the iterative receiving method according to the present invention with the estimated interference signals ,
- the superposition of the interference signals to the “useful signals” is symbolized in FIG. 4 by adders 44a, 44b.
- the same signals are present at the output of the adders 44a, 44b, however in a time-discrete representation, as at the output of the samplers 40a, 40b of FIG. 3, but without the white noise of the receiving antenna, which is added by the adders 34a, 34b.
- the noise vectors n (1) and n (2) are not correlated with one another and that the variance of all noise samples is ⁇ 2 N 0 / T s .
- first reception signal y ⁇ c which is the interference signal received signal from the first transmitter
- second reception signal y ( s 2 ⁇ c ) which is the interference signal synchronized reception signal with the second transmitter is.
- the receiving device includes a receiving antenna 50 and any known receiver front end 52 to accomplish a conversion of the received RF signal from the antenna 50 to baseband.
- the output signal of the receiver front end 52 is fed to a scanner 40 which comprises the first scanner 40a and the second scanner 40b.
- the first sampler 40a is controlled with respect to its sampling times by means of a synchronization signal 41a in order to achieve a sampling synchronized with the first transmitter 16a in FIG. 1.
- the second scanner is controlled by a synchronization signal 41b in order to obtain a scan of the received signal synchronized to the second transmitter 16b in FIG. 1.
- a first received signal is present at the output of the scanner 40a, but this is disturbed by interference from the second transmitter, as has been explained with reference to FIG. 4.
- a second received signal is present at the output of the second scanner, but is disturbed by interference from the first transmitter.
- the first received signal at the output of the first scanner 40a a decoder 54 supplied.
- the second receive signal is also supplied to decoder 54 to provide a first receive subset at a first output 56a associated with the first subset of code units on line 14a of the transmitter of FIG. 1.
- the decoder 54 provides on the output side on a second output line 56b a second receive subgroup of code units which is assigned to the second subgroup of code units on line 14b of the transmitting device of FIG. 1.
- the first reception subgroup and the interference-disturbed second reception subgroup are fed to a calculation device 58 in order to calculate a first interference signal on the basis of the second reception subgroup and to calculate a second interference signal based on the first reception subgroup.
- Both the first interference signal and the second interference signal are fed to an interference reduction device 60 and subtracted from the first received signal at the output of the first scanner or from the second received signal at the output of the second scanner, as is shown by subtractors 60a, 60b in FIG. 1 is shown schematically.
- a controller 62 is connected to the decoder 54 to control the decoder 54 to decode and base an improved first receive signal output from the interference reduction device 60 and an improved second receive signal output from the interference reduction device 60 outputs the information word on which the received signals are based with the plurality of information units on the improved first received signal and the improved second received signal on the output side.
- the controller 62 is also operative to decide whether one iteration is sufficient or whether one or more iteration steps should follow.
- the information word with the plurality of information units is output immediately using the decoded improved first signal and the decoded improved second signal, as represented by two dashed arrows 55a, 55b.
- the first reception subgroup is determined from the improved first signal and the improved second signal, as represented by dashed arrows 55d and 55c, and is used using the improved first signal and the improved second signal , as shown by arrows 55e and 55f, calculates the second receive subset.
- a now improved first interference signal and an improved second interference signal are again determined by the calculation device 58 and subtracted again in the interference reduction device from the first received signal or from the second received signal in order to have a further improved one at the output of the interference reduction device for this iteration step to determine the first signal and further improved second signal.
- the controller 62 now determines that the iteration is to be terminated because the predetermined iteration termination criterion has been met, the information word is immediately used using the further improved first signal and decoded and further improved second signal and output. For the second iteration too, the information word is thus calculated directly using the further improved first signal and the further improved second signal, but is still determined on the basis of the improved first signal and improved second signal obtained in the first iteration, especially since the further improved first signal and the further improved second signal based on the improved first signal or improved second signal.
- FIG. 5 A preferred exemplary embodiment of the receiving device shown in FIG. 5 is shown below with reference to FIG. 6.
- the same reference numerals mean the same elements.
- the scanner 40 is not shown in FIG. 6 in comparison to FIG. 5.
- the receiver of FIG. 6 is designed to receive and decode received signals that have been generated on the basis of transmission signals from the transmitter shown in FIG. 2.
- the decoding device 54 comprises a demapper 541a, 541b for each reception branch.
- the demapper receives complex samples on the input side, e.g. B. voltage values that are converted in the demapper 541a, 541b into extrinsic demapping probabilities.
- the complex sample value which represents a modulation symbol y, is thus converted into two extrinsic demapping probabilities by the demapper, for example 541a, the two probabilities standing for whether the two code units which together result in the examined QPSK symbol each have one Are 0 or a 1.
- the vector of extrinsic demodulation probabilities at the output of the demapper 541a or 541b is then fed into a de-interleaver 542a or 542b in order to undo the permutation carried out in the transmitter (elements 20a, 20b from FIG. 2) ,
- a vector of pre-decoding probabilities results, which has the same length as the vector at the input of the devices 542a or 542b.
- the pre-decoding probabilities for the first receiving subgroup of code units (device 543a) and the second receiving subgroup of code units (543b) are thus present at the output of the serial / parallel converters 543a or 543b.
- a decoder designed in this way provides, for example for a soft-in-soft-out decoder, a decoded first reception subgroup of code units, which is fed into a parallel / serial converter 544a, and a decoded second reception subgroup of code units which is fed into the parallel / serial converter 544b to make the parallel output of the SISO decoder serial.
- soft-in-soft-out decoders can be used instead of the BCJR-type SISO decoder.
- decoders can also be used which do not calculate with probabilities, but where the demapper already makes a hard 0/1 decision.
- the concept according to the invention is particularly suitable for soft decoding, in such a way that the preferred demapper does not convert sample values into code units per se but into probabilities for code units. In principle, however, it is equivalent whether the code units per se or the probabilities for the code units are used. Therefore, unless otherwise stated, when referring to code units hereinafter, probabilities for code units are also referred to simultaneously.
- delay elements 545a, 545b are shown in FIG. 6, which are intended to symbolize that the post-decoding probabilities for the first and second decoded received subgroup of code units for further processing are only available in the next iteration step .
- the vector of post decoding Probabilities for a specific iteration step i is again subjected to an interleaving operation by means of interleaver 546a, 546b in order to obtain permuted post-decoding probabilities, which are each fed into an estimating device, which is designated in FIG.
- the estimators 547a, 547b thus again represent complex 4-valued symbols.
- the estimators can thus be regarded as “soft” QPSK mappers, with the difference that the QPSK mappers of FIG. actually receive bits, while the estimators 547a, 547b in FIG. 6 receive probabilities for bits on the input side.
- the output lines of the estimators 547a, 547b of FIG. 6 thus correspond to the lines 56a and 56b of FIG. 5.
- the decoder 54 which is shown in principle in FIG. 5, thus contains when FIG. 5 and FIG. 6 are compared , mapping, de-interleaving, SISO decoding, interleaving post-decoding probabilities and the functionality of estimators 547a, 547b.
- the first receiving subgroup of code units at the output of the decoder 54 is present as a QPSK symbol as in FIG. 6 or, if a different modulation is used, as a different modulation symbol or, if no modulation is used, as a direct one Subset of code units. It is apparent to those skilled in the art that the type of modulation is not essential for the interference reduction concept according to the invention, although QPSK modulation / demodulation is preferred.
- the first and second receive subgroups of code units which the decoder 54 outputs can thus either be a direct receive subgroup with actually two or more separate code units or, as is the case in FIG.
- a receive subgroup of Code units the subgroup, however, being implemented as a symbol which depends on the two or more code units of the subgroup, the symbol in FIG. 6 being a “soft” QPSK symbol at the output of the estimator 547a or 547b.
- the calculation device includes multipliers 581a, 581b to take channel fading into account for both branches.
- the calculation device includes the transmission functions 582a, 582b introduced by the discrete-time representation to take into account the intersymbol interference due to the non-synchronism of the interference signal with the reception signal.
- the interference reduction device in which the first interference signal on line 583a is fed to adder 60a, while the second interference signal on line 583b is fed to second adder 60b, improved first and second reception signals on input lines 61a and 61b are fed into the decoder 54 generated.
- the demapper 541a and the demapper 541b are designed as special demappers which carry out the demapping function using page information.
- the page information is also supplied from the SISO decoder and is referred to in FIG. 6 as extrinsic decoding probabilities p C / extrdec [i].
- the extrinsic decoding probabilities become both for the first branch (1) and for the second Branch (2) determined from the post-decoding probabilities in a known manner.
- the determination of the extrinsic decoding probabilities from the post-decoding probabilities for the first and the second subset of code units is known in the art. Reference is made to Joachim Hagenauer, Elke Offer and Lutz Papke, "Iterative Decoding of Binary Block and Convolutional Codes", IEEE Trans. Inform. Theory, pages 429 - 437, 1996.
- the extrinsic decoding probabilities are fed to a first parallel / serial converter 550a for the first branch and a second parallel / serial converter 550b for the second branch and also, as described above with regard to delays 545a, 545b, by means of delay devices 551a or 551b delayed to indicate that this is an iteration loop.
- the extrinsic decoding probabilities are then permuted in interleavers 552a, in accordance with the same rule as is carried out in interleavers 546a and 546b or in the interleavers shown in FIG. 2.
- the permuted extrinsic decoding probabilities which are now referred to as pre-demapping probabilities, as can be seen from FIG. 6, are then supplied to demappers 541a, 541b as side information in order to perform the demapping function compared to a demapper without side information improve in order to ultimately achieve a better bit error rate at the output of the decoder.
- the controller 62 If the controller 62 has determined that an iteration termination criterion is met, it will drive the SISO decoder 540 to output post-decoding probabilities for the individual information units at an output. The post-decoding probabilities are then fed to a threshold value decision 555 in order to add the decoded information word ü obtained, which is ultimately fed into an information sink 62.
- the decoder 540 of FIG. 6 is designed as a soft-in / soft-out channel decoder (SISO decoder), which preferably uses the BCJR algorithm in order to obtain so-called soft estimates for the interference signal .
- SISO decoder any other trellis decoder that can decode the first and the second received signal can be used to generate a first receive subgroup of code units, which is assigned to the first transmit subgroup of code units, and a second receive subgroup of code units, which is assigned to the second transmission subgroup of code units.
- SISO decoder is preferably used which can provide post-decoding probabilities for the first and second receive subgroups from pre-decode probabilities for the first and second receive subgroups.
- the output of the decoder from the (i-l) th iteration is used for the interference reduction.
- the last index of a variable used for the recipient designates the iteration in which the variable was calculated. It is assumed that the channel decoder has calculated post-decoding probabilities in iteration i-1, where p c , postdec [k] [i-1] represents the probability that the transmitted code bit c [k] is 1. For reasons of clarity, but without restricting generality, the probability of an event is always considered below, in that the respective bit is a logical 1.
- the SISO decoder has also calculated the assigned extrinsic probabilities p c , e ⁇ trdec ti ⁇ 1] for the bits in the code word c.
- both the post-decoding probabilities and the extrinsic probabilities are divided into two streams or subgroups and converted in parallel / serial, so that the vectors p r c, ""'. Postd J ec "-iI and p r c ( l 2I '.postd_, ec "-iJ the post-decoding-
- Probabilities for the bits in the code words c (1) and c (2) of satellites 1 and 2 are obtained. The same is obtained for the assigned extrinsic probabilities, so that corresponding vectors with extrinsic probabilities arise. Both vectors are permuted by the corresponding interleaver shown in FIG. 6.
- the notation p_ (l ,, fil and p.-, 2 ,. Fil was used because these extrinsic probabilities calculated by the decoder are used as pre-demapping probabilities.
- the post-decoding probabilities for the permuted code bits can now be used to reconstruct the vectors x (1) and x ⁇ 2) of the transmitted QPSK symbols.
- the interference signals yj, '' and yj 2 , ' are first reconstructed in that x (l) [i] or x (2) [i] element by element with the estimated fading coefficients ä (l) and ä ⁇ 2 ) are multiplied. Then the results y (l) [i] and y (2) [i] obtained are each filtered with H (l ⁇ 2) (z) and H (2 ⁇ l) (z).
- These filters represent the estimates of the receiver for the filters H (1 ⁇ 2) (z) and H (2 ⁇ 1) (z), which are in the discrete-time transmission model shown in FIG. 4 are responsible for the interference. Therefore, these filters have the following impulse responses:
- ⁇ 2 is the variance of the QPSK constellation in the transmitter.
- the demapper 541a or 541b of FIG. 6 is discussed in more detail below.
- the total power of the mean-free distortion d (1) [j] [i], which lies in a sample y (l) [jl-], is the sum of the residual interference power ( ⁇ ⁇ jjji] j and the noise power ⁇ 2 complex random variable dj l) [jIi] + jdg
- d (1) [j] [i] see it as a two-dimensional real Gauss'
- mapping in the transmitter of a pair (c ⁇ l) [2j + l], c (l) [2j]) of successive bits in the code word c (l) into a complex-valued QPSK symbol is represented by x (c (l) [2j + l], c (l) [2j]).
- the demapper calculates the post-demapping probability as follows:
- the demapper calculates the following extrinsic probabilities and forwards them to the decoder:
- gray mapping is used in the mappers 22a, 22b of FIG. 2. This means that a code bit of a pair (c ⁇ ,, ⁇ ] ') is the I component of the
- Bit c (l) [2j + l] is mapped to the Q component. The following is also assumed: ⁇ d consult )
- _2j - + - 1 Ji] only from the Q-
- Component depends on y (l) [jfi]. This size is independent of the pre-demapping probability p E ( " rcd ( . M [2 jfi]) of the code bit in the I component.
- pre-demapping probability p_ 11 2jJi] of the code bit in the I component.
- Fig. 10 shows the probability density function pdf (y (1) DI '] lP H U ⁇ " redcm [i]), while Fig. 11 shows P £ ( " , extrde ⁇ [2j + l] [i].
- the demapping for the second satellite is basically carried out in the same way as the demapping for the first satellite extrinsic
- interleavers are preferred for an exemplary embodiment of the present invention:
- the channel for the transmission system is a channel with fading. Therefore, severe fading symptoms that are also known as deep fades, by moving the symbols concerned to different locations in the code word.
- the demapper and the decoder iteratively exchange extrinsic probabilities. Probabilities that are adjacent in the corresponding output vectors of an element are statistically dependent. On the other hand, it is assumed, however, that neighboring probabilities at the input of an element are statistically independent. Optimal behavior is achieved for every iterative system if this assumption of the statistical independence of the input symbols is fulfilled. It is therefore preferred to use an interleaver to distribute adjacent elements in the output vector of one element to different locations or elements at the input of the other element. This procedure is usually also referred to as "decorrelation of the extrinsic probabilities".
- the distortion in y (l) [i] and y ⁇ 2) [i] is actually colored. For example, if a mistake in interference reduction is made and the distortion is very large, then not only one QPSK symbol will be seriously disturbed but several successive QPSK symbols. As with a fading channel, these error bursts must also be distributed by distributing them to different locations in the code word.
- interleaver As an interleaver, s-random interleavers are also preferred, as has already been stated. Because of their spreading limitation, they ensure that neighboring elements at their input are actually brought to remote output elements, so that deep fades and error bursts are destroyed. On the other hand It turned out that a random, ie non-regular, interleaver behaves better in iterative systems than a regular structure.
- Decoding probabilities for the sub-code words c (1) and c (2) are finally converted to serial / parallel and serve as an input to the SISO decoder. Based on these pre-decoding probabilities p c , p redec [i], the new post-decoding probabilities p c , P ostdec [i] and the extrinsic probabilities p c , ex trdec [i] can be calculated.
- An information word with a length of 494 information units can be used as a dimensioning example.
- LOS Line Of Sight
- Rayleigh fading component with a corresponding variance.
- the standardized maximum Doppler frequency of these processes can be assumed to be 0.01.
- Corresponding rice factors can be specified for the two statistically independent rice fading processes.
- 40 different known concepts are used for the synchronization of the scanner.
- can such as B. training sequences that are sent from the two different transmitters and from which a scanner can synchronize itself to the corresponding transmitter.
- B. training sequences that are sent from the two different transmitters and from which a scanner can synchronize itself to the corresponding transmitter.
- customary channel estimation methods can be used, which also work with training sequences.
- there are also blind estimation methods that can achieve channel estimation without previously known training sequences.
- the transfer functions of these filters can be set to "1" if an ideal synchronization is assumed. Depending on the application, this transfer function can also be estimated empirically.
Abstract
Description
Claims
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AT03717328T ATE314761T1 (de) | 2002-05-10 | 2003-05-06 | Diversitätsverfahren und vorrichtung |
JP2004504441A JP4098773B2 (ja) | 2002-05-10 | 2003-05-06 | 受信装置及び受信方法 |
AU2003222317A AU2003222317A1 (en) | 2002-05-10 | 2003-05-06 | Diversity method and device |
DE50302072T DE50302072D1 (de) | 2002-05-10 | 2003-05-06 | Diversitätsverfahren und vorrichtung |
US10/985,566 US7372802B2 (en) | 2002-05-10 | 2004-11-10 | Message communication via channels having strong fading |
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AT (1) | ATE314761T1 (de) |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008505558A (ja) * | 2004-07-01 | 2008-02-21 | クアルコム インコーポレイテッド | 先進mimoインターリービング |
EP2690814A1 (de) * | 2003-11-21 | 2014-01-29 | Panasonic Corporation | Mehrfachantennenvorrichtung mittels verschiedener Interleaving-Muster |
WO2021001551A3 (de) * | 2019-07-03 | 2021-03-04 | Innovationszentrum für Telekommunikationstechnik GmbH IZT | Empfänger zum empfangen eines kombinationssignals mit berücksichtigung einer inter-symbol-interferenz, verfahren zum empfangen eines kombinationssignals und computerprogramm |
Families Citing this family (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102004032222B4 (de) | 2004-07-02 | 2011-02-10 | Infineon Technologies Ag | Empfänger eines Positionsbestimmungssystems mit verbesserter Sensitivität und Verfahren zur Positionsbestimmung |
CA2601151A1 (en) * | 2005-03-14 | 2006-09-21 | Telcordia Technologies, Inc. | Iterative stbicm mimo receiver using group-wise demapping |
EP1746756B1 (de) * | 2005-07-21 | 2013-01-16 | STMicroelectronics Srl | Verfahren und System zur Signaldekodierung, entsprechender Empfänger und Rechnerprogrammprodukt |
US7636397B2 (en) * | 2005-09-07 | 2009-12-22 | Mclaughlin Michael | Method and apparatus for transmitting and receiving convolutionally coded data for use with combined binary phase shift keying (BPSK) modulation and pulse position modulation (PPM) |
FR2937480B1 (fr) * | 2008-10-22 | 2011-05-06 | Commissariat Energie Atomique | Turbocodeur distribue pour canaux a evanouissements par blocs |
US8448033B2 (en) * | 2010-01-14 | 2013-05-21 | Mediatek Inc. | Interleaving/de-interleaving method, soft-in/soft-out decoding method and error correction code encoder and decoder utilizing the same |
US8744026B2 (en) * | 2010-10-13 | 2014-06-03 | Telefonakktiebolaget Lm Ericsson (Publ) | Method and apparatus for interference suppression using a reduced-complexity joint detection |
JP5578617B2 (ja) | 2010-10-18 | 2014-08-27 | パナソニック インテレクチュアル プロパティ コーポレーション オブ アメリカ | 送信方法、送信装置、受信方法および受信装置 |
US8724715B2 (en) | 2011-02-17 | 2014-05-13 | Massachusetts Institute Of Technology | Rateless and rated coding using spinal codes |
US9160399B2 (en) | 2012-05-24 | 2015-10-13 | Massachusetts Institute Of Technology | System and apparatus for decoding tree-based messages |
US9219631B2 (en) * | 2012-09-21 | 2015-12-22 | Kratos Integral Holdings, Llc | System and method for increasing spot beam satellite bandwidth |
US10135518B2 (en) * | 2012-11-15 | 2018-11-20 | Novelsat Ltd. | Echo cancellation in communication transceivers |
US9270412B2 (en) * | 2013-06-26 | 2016-02-23 | Massachusetts Institute Of Technology | Permute codes, iterative ensembles, graphical hash codes, and puncturing optimization |
US9967021B2 (en) | 2016-07-14 | 2018-05-08 | Suntrust Bank | Systems and methods for signal cancellation in satellite communication |
CN108206798B (zh) * | 2016-12-20 | 2020-07-28 | 北京大学 | 一种抑制相邻发射机干扰的通信方法 |
FR3063856B1 (fr) * | 2017-03-09 | 2019-04-26 | Commissariat A L'energie Atomique Et Aux Energies Alternatives | Systeme d'emission/reception utilisant une modulation conjointe orthogonale-lineaire |
US10200071B1 (en) * | 2017-08-07 | 2019-02-05 | Kratos Integral Holdings, Llc | System and method for interference reduction in radio communications |
DE102018202648B4 (de) * | 2018-02-21 | 2019-10-17 | Innovationszentrum für Telekommunikationstechnik GmbH IZT | Empfänger und Verfahren zum Empfangen eines Kombinationssignals unter Verwendung von Wahrscheinlichkeitsdichtefunktionen |
DE102019209801A1 (de) * | 2019-07-03 | 2021-01-07 | Innovationszentrum für Telekommunikationstechnik GmbH IZT | Empfänger zum Empfangen eines Kombinationssignals mit Berücksichtigung einer Inter-Symbol-Interferenz und niedriger Komplexität, Verfahren zum Empfangen eines Kombinationssignals und Computerprogramm |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5341395A (en) * | 1992-11-24 | 1994-08-23 | At&T Bell Laboratories | Data recovery technique for asynchronous CDMA systems |
DE19647833B4 (de) * | 1996-11-19 | 2005-07-07 | Deutsches Zentrum für Luft- und Raumfahrt e.V. | Verfahren zur gleichzeitigen Funkübertragung digitaler Daten zwischen mehreren Teilnehmerstationen und einer Basisstation |
US5991273A (en) * | 1997-05-01 | 1999-11-23 | Nortel Networks Corporation | Determining SINR in a communications system |
US5887035A (en) * | 1997-10-31 | 1999-03-23 | Ericsson, Inc. | Method for joint equalization and detection of multiple user signals |
US6304618B1 (en) * | 1998-08-31 | 2001-10-16 | Ericsson Inc. | Methods and systems for reducing co-channel interference using multiple timings for a received signal |
US20020110206A1 (en) * | 1998-11-12 | 2002-08-15 | Neal Becker | Combined interference cancellation with FEC decoding for high spectral efficiency satellite communications |
US6314289B1 (en) | 1998-12-03 | 2001-11-06 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Apparatus and method for transmitting information and apparatus and method for receiving information |
US6574235B1 (en) | 1999-08-12 | 2003-06-03 | Ericsson Inc. | Methods of receiving co-channel signals by channel separation and successive cancellation and related receivers |
JP2001127649A (ja) * | 1999-10-29 | 2001-05-11 | Mitsubishi Electric Corp | 通信装置および通信方法 |
US6847688B1 (en) * | 2000-10-30 | 2005-01-25 | Ericsson Inc. | Automatic frequency control systems and methods for joint demodulation |
FR2821217B1 (fr) * | 2001-02-21 | 2003-04-25 | France Telecom | Procede et systeme de codage-decodage iteratif de flux de donnees numeriques codees par combinaisons spatio-temporelles, en emission et reception multiple |
US6691263B2 (en) * | 2001-05-03 | 2004-02-10 | Agere Systems Inc. | Interative decoding based on dominant error events |
US20030161258A1 (en) * | 2002-02-22 | 2003-08-28 | Jianzhong Zhang | Apparatus, and associated method, for a multiple-input, multiple-output communications system |
US7254192B2 (en) * | 2002-07-12 | 2007-08-07 | Texas Instruments Incorporated | Iterative detection in MIMO systems |
-
2002
- 2002-05-10 DE DE10220892A patent/DE10220892A1/de not_active Withdrawn
-
2003
- 2003-05-06 CN CNB038105551A patent/CN100382475C/zh not_active Expired - Fee Related
- 2003-05-06 DE DE50302072T patent/DE50302072D1/de not_active Expired - Lifetime
- 2003-05-06 AT AT03717328T patent/ATE314761T1/de active
- 2003-05-06 AU AU2003222317A patent/AU2003222317A1/en not_active Abandoned
- 2003-05-06 WO PCT/EP2003/004759 patent/WO2003096599A1/de active IP Right Grant
- 2003-05-06 EP EP03717328A patent/EP1504557B1/de not_active Expired - Lifetime
- 2003-05-06 JP JP2004504441A patent/JP4098773B2/ja not_active Expired - Fee Related
-
2004
- 2004-11-10 US US10/985,566 patent/US7372802B2/en not_active Expired - Fee Related
Non-Patent Citations (4)
Title |
---|
BRUNEL L ET AL: "Iterative interference cancellation scheme with pilot-aided space-time estimation in DS-CDMA systems", VTC FALL 2001. IEEE 54TH. VEHICULAR TECHNOLOGY CONFERENCE. PROCEEDINGS. ATLANTIC CITY, NJ, OCT. 7 - 11, 2001, IEEE VEHICULAR TECHNOLGY CONFERENCE, NEW YORK, NY: IEEE, US, vol. 1 OF 4. CONF. 54, 7 October 2001 (2001-10-07), pages 197 - 201, XP010562673, ISBN: 0-7803-7005-8 * |
SU H-J ET AL: "SPACE-TIME TURBO CODES WITH FULL ANTENNA DIVERSITY", IEEE TRANSACTIONS ON COMMUNICATIONS, IEEE INC. NEW YORK, US, vol. 49, no. 1, 1 January 2001 (2001-01-01), pages 47 - 57, XP001038827, ISSN: 0090-6778 * |
WIJK VAN D J ET AL: "FADING CORRELATION AND ITS EFFECT ON THE CAPACITY OF SPACE-TIME TURBO CODED DS/SDMA SYSTEMS", MILCOM 1999. IEEE MILITARY COMMUNICATIONS CONFERENCE PROCEEDINGS. ATLANTIC CITY, NJ, OCT. 31 - NOV. 3, 1999, IEEE MILITARY COMMUNICATIONS CONFERENCE, NEW YORK, NY: IEEE, US, vol. VOL 1 OF 2 CONF. 18, 31 October 1999 (1999-10-31), pages 538 - 542, XP000921974, ISBN: 0-7803-5539-3 * |
YONG W ET AL: "MULTIUSER DETECTOR WITH TRANSMIT DIVERSITY IN THE CONVOLUTIONALLY CODED DS/CDMA SYSTEMS", VTC 2000-SPRING. 2000 IEEE 51ST. VEHICULAR TECHNOLOGY CONFERENCE PROCEEDINGS. TOKYO, JAPAN, MAY 15-18, 2000, IEEE VEHICULAR TECHNOLGY CONFERENCE, NEW YORK, NY: IEEE, US, vol. 1 OF 3. CONF. 51, 15 May 2000 (2000-05-15), pages 552 - 555, XP000970680, ISBN: 0-7803-5719-1 * |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2690814A1 (de) * | 2003-11-21 | 2014-01-29 | Panasonic Corporation | Mehrfachantennenvorrichtung mittels verschiedener Interleaving-Muster |
US8724729B2 (en) | 2003-11-21 | 2014-05-13 | Harris Corporation | Interleaver, interleaving method, transmission apparatus, and transmitting method |
JP2008505558A (ja) * | 2004-07-01 | 2008-02-21 | クアルコム インコーポレイテッド | 先進mimoインターリービング |
JP2012075180A (ja) * | 2004-07-01 | 2012-04-12 | Qualcomm Inc | 先進mimoインターリービング |
US9008199B2 (en) | 2004-07-01 | 2015-04-14 | Qualcomm Incorporated | Advanced MIMO interleaving |
WO2021001551A3 (de) * | 2019-07-03 | 2021-03-04 | Innovationszentrum für Telekommunikationstechnik GmbH IZT | Empfänger zum empfangen eines kombinationssignals mit berücksichtigung einer inter-symbol-interferenz, verfahren zum empfangen eines kombinationssignals und computerprogramm |
EP4199441A1 (de) | 2019-07-03 | 2023-06-21 | Innovationszentrum für Telekommunikationstechnik GmbH IZT | Empfänger zum empfangen eines kombinationssignals mit berücksichtigung einer inter-symbol-interferenz, verfahren zum empfangen eines kombinationssignals und computerprogramm |
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US20050111347A1 (en) | 2005-05-26 |
CN100382475C (zh) | 2008-04-16 |
JP2005531944A (ja) | 2005-10-20 |
DE10220892A1 (de) | 2003-12-18 |
CN1653740A (zh) | 2005-08-10 |
US7372802B2 (en) | 2008-05-13 |
JP4098773B2 (ja) | 2008-06-11 |
DE50302072D1 (de) | 2006-02-02 |
EP1504557A1 (de) | 2005-02-09 |
EP1504557B1 (de) | 2005-12-28 |
AU2003222317A1 (en) | 2003-11-11 |
ATE314761T1 (de) | 2006-01-15 |
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