WO2002063779A2 - Low complexity data detection using fast fourier transform of channel correlation matrix - Google Patents
Low complexity data detection using fast fourier transform of channel correlation matrix Download PDFInfo
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- WO2002063779A2 WO2002063779A2 PCT/US2002/002400 US0202400W WO02063779A2 WO 2002063779 A2 WO2002063779 A2 WO 2002063779A2 US 0202400 W US0202400 W US 0202400W WO 02063779 A2 WO02063779 A2 WO 02063779A2
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- 239000011159 matrix material Substances 0.000 title claims abstract description 59
- 238000001514 detection method Methods 0.000 title claims description 48
- 239000013598 vector Substances 0.000 claims abstract description 45
- 238000000354 decomposition reaction Methods 0.000 claims abstract description 24
- 238000001228 spectrum Methods 0.000 claims abstract description 9
- 238000005070 sampling Methods 0.000 claims description 16
- 238000000034 method Methods 0.000 claims 20
- 238000013459 approach Methods 0.000 description 17
- 230000005540 biological transmission Effects 0.000 description 6
- 238000004088 simulation Methods 0.000 description 4
- 230000015556 catabolic process Effects 0.000 description 3
- 238000006731 degradation reaction Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 108010003272 Hyaluronate lyase Proteins 0.000 description 2
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- GVVPGTZRZFNKDS-JXMROGBWSA-N geranyl diphosphate Chemical compound CC(C)=CCC\C(C)=C\CO[P@](O)(=O)OP(O)(O)=O GVVPGTZRZFNKDS-JXMROGBWSA-N 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
- H04B1/7103—Interference-related aspects the interference being multiple access interference
- H04B1/7105—Joint detection techniques, e.g. linear detectors
- H04B1/71052—Joint detection techniques, e.g. linear detectors using decorrelation matrix
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
- H04B1/7103—Interference-related aspects the interference being multiple access interference
- H04B1/7105—Joint detection techniques, e.g. linear detectors
- H04B1/71055—Joint detection techniques, e.g. linear detectors using minimum mean squared error [MMSE] detector
Definitions
- the invention generally relates to wireless communication systems.
- the invention relates to data detection in a wireless communication system.
- Figure 1 is an illustration of a wireless communication system 10.
- the communication system 10 has base stations 12 x to 12 5 which communicate with user equipments (UEs) 14 j to 14 3 .
- UEs user equipments
- Each base station 12 ! has an associated operational area, where it communicates with UEs 14 x to 14 3 in its operational area.
- UEs user equipments
- CDMA code division multiple access
- TDD/CDMA time division duplex using code division multiple access
- multiple communications are sent over the same frequency spectrum. These communications are differentiated by their channelization codes.
- TDD/CDMA communication systems use repeating frames divided into time slots for communication. A communication sent in such a system will have one or multiple associated codes and time slots assigned to it. The use of one code in one time slot is referred to as a resource unit.
- a receiver in such a system must distinguish between the multiple communications.
- One approach to detecting such signals is multiuser detection. In multiuser detection, signals associated with all the UEs 14 x to 14 3 users, are detected simultaneously. Approaches for implementing multiuser detection include block linear equalization based joint detection (BLE-JD) using a Cholesky or an approximate Cholesky decomposition.
- BLE-JD block linear equalization based joint detection
- Another approach is single user detection.
- single user detection data is only recovered for a single user (one UE 14 j ). Based on the application, the single user detected data may have been sent using one or multiple codes.
- Approaches for implementing single user detection include block linear equalization using a Cholesky or an approximate Cholesky decomposition. These approaches have a high complexity. The high complexity leads to increased power consumption, which at the UE 14, results in reduced battery life. Accordingly, it is desirable to have alternate approaches to detecting received data.
- a combined signal is received over a shared spectrum in a time slot in a time division duplex communication system using code division multiple access. Each data signal experiences a similar channel response. The similar channel response is estimated. A matrix representing a channel of the data signals based on in part the estimated channel response is constructed. A spread data vector is determined based on in part a fast fourier transform (FFT) decomposition of a circulant version of the channel matrix. The spread data vector is despread to recover data from the received combined signal.
- FFT fast fourier transform
- Figure 1 is a wireless communication system.
- Figure 2 is a simplified transmitter and a single user detection receiver.
- Figure 3 is an illustration of a communication burst.
- Figure 4 is a flowchart of low complexity data detection.
- Figures 5-15 are graphs of the performance of low complexity data detection.
- FIG. 2 illustrates a simplified transmitter 26 and receiver 28 using low complexity data detection in a TDD/CDMA communication system.
- a transmitter 26 is in each UE 14 x to 14 3 and multiple transmitting circuits 26 sending multiple communications are in each base station 12 x to 12 5 .
- the low complexity data detector receiver 28 may be at a base station 12 l9 UEs 14 j to 14 3 or both.
- the receiver 28 can be used at a UE ⁇ 4 for either multiuser or single user detection of a medium to high data rate service, such as a 2 megabits per second (Mbs).
- Mbs 2 megabits per second
- the receiver 28 can also be used at a base station 12 1? when only a single UE 14j transmits in a time slot.
- the transmitter 26 sends data over a wireless radio channel 30.
- a data generator 32 in the transmitter 26 generates data to be communicated to the receiver 28.
- a modulation/spreading sequence insertion device 34 spreads the data and makes the spread reference data time-multiplexed with a midamble training sequence in the appropriate assigned time slot and codes for spreading the data, producing a communication burst or bursts.
- a typical communication burst 16 has a midamble 20, a guard period 18 and two data bursts 22, 24, as shown in Figure 3.
- the midamble 20 separates the two data bursts 22, 24 and the guard period 18 separates the communication bursts to allow for the difference in arrival times of bursts transmitted from different transmitters 26.
- the two data bursts 22, 24 contain the communication burst's data.
- the communication burst(s) are modulated by a modulator 36 to radio frequency (RF).
- An antenna 38 radiates the RF signal through the wireless radio channel 30 to an antenna 40 of the receiver 28.
- the type of modulation used for the transmitted communication can be any of those known to those skilled in the art, such as quadrature phase shift keying (QPSK) or an N-ary quadrature amplitude modulation (QAM).
- QPSK quadrature phase shift keying
- QAM N-ary quadrature amplitude modulation
- the antenna 40 of the receiver 28 receives various radio frequency signals.
- the received signals are demodulated by a demodulator 42 to produce a baseband signal.
- the baseband signal is processed, such as by a channel estimation device 44 and a low complexity data detection device 46, in the time slot and with the appropriate codes assigned to the received bursts.
- the channel estimation device 44 uses the midamble training sequence component in the baseband signal to provide channel information, such as channel impulse responses.
- the channel information is used by the data detection device 46 to estimate the transmitted data of the received communication bursts as hard symbols.
- the data detection device 46 uses the channel information provided by the channel estimation device 44 and the known spreading codes used by the transmitter 26 to estimate the data of the desired received communication burst(s).
- Low complexity data detection is explained in conjunction with the flowchart of Figure 4.
- 3GPP third generation partnership project
- UTRA universal terrestrial radio access
- That system is a direct sequence wideband CDMA (W-CDMA) system, where the uplink and downlink transmissions are confined to mutually exclusive time slots.
- the receiver 28 receives using its antenna 40 a total of K bursts that arrive simultaneously, 48.
- the K bursts are superimposed on top of each other in one observation interval. Some or all of the K bursts may arise from or go to the same users for higher data rate services.
- each data field of a time slot corresponds to one observation interval.
- a kf h burst of the K bursts uses a code of C ⁇ k) of length Q chips to
- N c (SF • N s + W - 1) .
- SE is the spreading factor. Since uplink signals may originate from multiple U ⁇ s 14 ⁇ 0 14 3 , each h ik) in the uplink may be distinct. For the downlink in the absence of transmit
- bursts pass through the same channel and have the same h (k) .
- the bursts from all users arrive superimposed as a single received vector , r_ .
- Some or all of the K bursts may be part of a multi-code transmission.
- the multi-user signal model consists of N c known received chips and
- kf h burst is the convolution of C_ ⁇ k) with h ⁇ k ) . Accordingly, (t ) is of length (SF+W-l)
- Equation 1 Equation 1
- a (k> is the channel response matrix for the kf h burst, which is an N c x N ⁇ matrix whose/ 1 column is the symbol-response of the element of d_ ⁇ k) .
- each column of A (k> has the same support, ( k , and
- n is a zero-mean noise vector with independent identical distribution (i.i.d.)
- Equation 2 becomes Equation 3, when written as a single matrix equation.
- A is the overall channel response matrix, which is a matrix of size
- d_ is the data vector, which is a column vector of length K - N s .
- Equation 2 and Equation 3 model the inter-symbol interference (ISI) and multiple- access interference (MAI) in the received vector, r .
- the signal models of Equations 1 , 2 and 3 are formulated for chip rate sampling, such as 3.84 Mega chips per second (Mcps) in 3GPP UTRA system.
- a receiver 28 may use over-sampling, such as a multiple chip rate sampling.
- a typical multiple chip rate sampling is twice the chip rate, although other multiples may be used.
- the received signal burst will be over-sampled generating multiple sampled sequences. Each sequence is sampled at the chip rate with different time offsets with respect to one another.
- the k" 1 burst passes through a channel with a known or estimated channel response, h m , for the m th sampled sequence.
- r m is the contribution of the
- Equation 4 the m th sampled chip vector r m ) are related by Equation 4.
- a ⁇ ] is the symbol response matrix for the m th sequence. It is a matrix of size
- Equation 5 is the overall, chip-rate, received vector, _ r m , of the m th sampled sequence. (k ) ,
- Equation 6 For an M multiple of chip rate sampling, a single matrix expression is per Equation 6.
- _ r is the received signal vector and is defined as per Equation 7.
- a ' is defined as per Equation 8.
- Equation 9 is Equation 6 rewritten as a summation form of i bursts. - ⁇ Equation 9
- Equation 9 can be rewritten as Equation 10.
- C ⁇ ' is code sequence ofthe ⁇ burst.
- H /(* ') is the channel response for the f h sequence, which is defined for M multiple chip rate sampling per Equation 11.
- Equation 12 Equation 12 rewritten as a single matrix expression.
- C is the code matrix.
- H c ' is per Equation 14.
- H cm is the channel response for the m' h sampled sequence.
- the matrix structure of each H is per Equation 15, 52.
- s ⁇ Cd Equation 17 [0041] is the spread data chip vector.
- C is the code vector.
- Equation 16 determines_ is to use a zero forcing (ZF) solution of Equation 16 as per Equation 18.
- K c ' is the hermitian of H c ' . Another approach is to use a minimum
- MMSE mean square error
- ⁇ 2 is the noise variance.
- / is the identity matrix.
- Equation 17 or 18 for s the solution of Equation 17 is obtained by despreading, as represented by Equation 20, 56.
- Equation 18 The following approaches to solve Equations 18 and 19 for s use a fast fourier transform (FFT) decomposition of either a circulant approximation of the channel correlation matrix, R, or the channel response matrix, H C ' , 5 ⁇ .
- FFT fast fourier transform
- Using either matrix requires an approximation; however, using the channel response matrix, H c ' , also requires truncation of the last W-l rows of the matrix to make it square. Accordingly, to eliminate degradation due to truncation, the channel correlation matrix, R, is preferably used.
- a FFT decomposition of the channel correlation matrix, R is performed as follows. For a ZF approach, R is defined as per Equation 21.
- R is defined as per Equation 22.
- Equations 18 and 19 are rewritten in terms of R as per Equations 24 and
- the matrix-vector multiplication R s_ can be viewed as a linear combination of column vectors of the channel correlation matrix, R, weighted by the corresponding elements of data chip vector ⁇ , as per Equation 26.
- *£ ⁇ S j + 8_ 2 +-.+ £ w + + ⁇ i w +1 +--+ ⁇ . ⁇ i w SF
- g . is the i column of the channel correlation matrix R.
- s t is the i ⁇ th
- Equation 27 [0052] The first column, q , has the full non-zero elements without any
- the circulant matrix, R cir is defined by its first column q .
- Equation 28 the channel correlation matrix, R, using the permutation operator or index vector as defined by Equation 28.
- a circulant matrix is also defined by the W h column g of
- channel correlation matrix R.
- any column greater than W h column may be used with a proper index vector (permutation vector).
- the solved spread data chip vector ⁇ is required to be inverse permuted by the index vector ⁇ p as per Equation 30.
- Equation 31 is the FFT decomposition of matrix R cir .
- Dp is the P-point FFT matiix and A R is diagonal matrix, whose
- a R is defined as
- a R diag(D P q) .
- Equation 32 Matched filtering, H c W r , is represented by Equation 32.
- H cm , m 1,2,..., M , are circulant matrixes. Each matrix can be decomposed into three FFT matrix multiplication as per Equation 33.
- Equation 35 To recover the data chip vector s_ , Equation 35 is used.
- Equation 35 becomes Equation 36.
- F (s) is determined.
- the spread data vector, s_ is determined. If used for multi-user detection in the downlink or a single user solely uses one time slot in the uplink, s is despread by using all of the codes to recover the transmitted data d_ as soft symbols. If used for single user
- ⁇ is despread using that user's codes to recover that user's data as soft symbols. Hard decisions are made to convert the soft symbols to hard symbols.
- PFA prime factor algorithm
- radix-2 a radix-2 algorithm
- a PFA is considered more efficient than a radix-2 algorithm when a non-power-of-two number of FFT points is used
- the following complexity analysis is based on aradix-2 FFT implementation for simplicity.
- the complexity based on radix-2 algorithm can be considered as the worst case. Additional improvement in complexity is obtainable when PFA is used.
- Zero- padding radix-2 FFT implementation entails the zero-padding the first column of H cm ,
- the length of a data field is 976 chips for burst type 1 in a TDD burst specified by 3GPP W-CDMA standard.
- P is the radix-2 integer.
- the total complexity of the data detection including despreading is per Equations 42 or 43.
- Table 1 MROPS of a full-burst using low complexity data detection for burst type 1 at chip rate sampling.
- BER bit error rate
- single-code transmission uses 16 resource units per time slot while the multi-code transmission uses only 12 resource units in each time slot.
- Using only 12 codes produces less interference and therefore better BER.
- FFT-R channel correlation matrix
- the FFT-R based approach is identical to the block linear equalization structure.
- the proposed FFT-R based approach and the approach based on FFT of the channel response matrix (FFT-H) are identical to each other at the chip rate sampling.
- FFT-H is compared to an ideal single user bond, a worst case matched filtering, BLE- JD and single user detection with BLE using an approximate Cholesky decomposition.
- the BER range was typically between 1 % and 10%.
- SNR signal to noise ratio
- MF SNR performance enhancement over matched filtering
- Low complexity data detection also performs well in an additive white gaussian noise (AWGN) channel environment.
- AWGN additive white gaussian noise
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Priority Applications (10)
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KR1020037010376A KR100605332B1 (en) | 2001-02-06 | 2002-01-28 | Low complexity data detection using fast fourier transform of channel correlation matrix |
DE60212334T DE60212334T2 (en) | 2001-02-06 | 2002-01-28 | DATA DISCUSSION WITH LOW COMPLEXITY USING FOURTIER TRANSFORMATION OF A CHANNEL CORRELATION MATRIX |
CA002437660A CA2437660A1 (en) | 2001-02-06 | 2002-01-28 | Low complexity data detection using fast fourier transform of channel correlation matrix |
KR1020037013881A KR100759297B1 (en) | 2001-02-06 | 2002-01-28 | Low complexity data detection using fast fourier transform of channel correlation matrix |
MXPA03007025A MXPA03007025A (en) | 2001-02-06 | 2002-01-28 | Low complexity data detection using fast fourier transform of channel correlation matrix. |
EP02709196A EP1358718B1 (en) | 2001-02-06 | 2002-01-28 | Low complexity data detection using fast fourier transform of channel correlation matrix |
JP2002563610A JP3897302B2 (en) | 2001-02-06 | 2002-01-28 | Low complexity data detection using fast Fourier transform of channel correlation matrix |
AU2002243695A AU2002243695A1 (en) | 2001-02-06 | 2002-01-28 | Low complexity data detection using fast fourier transform of channel correlation matrix |
NO20033476A NO20033476L (en) | 2001-02-06 | 2003-08-05 | Low complexity data detection using fast Fourier transformation of channel correlation matrix |
HK04107106A HK1064526A1 (en) | 2001-02-06 | 2004-09-20 | Low complexity data detection using fast fourier transform of channel correlation matrix |
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US60/268,587 | 2001-02-15 | ||
US09/814,346 US6885654B2 (en) | 2001-02-06 | 2001-03-22 | Low complexity data detection using fast fourier transform of channel correlation matrix |
US09/814,346 | 2001-03-22 |
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EP (1) | EP1358718B1 (en) |
JP (2) | JP3897302B2 (en) |
KR (2) | KR100759297B1 (en) |
CN (1) | CN1295886C (en) |
AT (1) | ATE330372T1 (en) |
AU (1) | AU2002243695A1 (en) |
CA (1) | CA2437660A1 (en) |
DE (1) | DE60212334T2 (en) |
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HK (1) | HK1064526A1 (en) |
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Cited By (3)
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---|---|---|---|---|
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US7386033B2 (en) | 2003-01-10 | 2008-06-10 | Interdigital Technology Corporation | Communication system with receivers employing generalized two-stage data estimation |
US7796680B2 (en) | 2004-02-12 | 2010-09-14 | Nec Corporation | Mobile communication system and wireless apparatus to be used for the same |
Families Citing this family (43)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6885654B2 (en) * | 2001-02-06 | 2005-04-26 | Interdigital Technology Corporation | Low complexity data detection using fast fourier transform of channel correlation matrix |
US7027489B2 (en) * | 2001-04-06 | 2006-04-11 | Interdigital Technology Corporation | Iterative fast fourier transform error correction |
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US7443908B2 (en) * | 2001-11-26 | 2008-10-28 | Stmicroelectronics S.R.L. | Low complexity detection in digital receivers |
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US7257170B2 (en) * | 2002-08-21 | 2007-08-14 | Texas Instruments Incorporated | Channel norm-based ordering and whitened decoding for MIMO communication systems |
US8194770B2 (en) * | 2002-08-27 | 2012-06-05 | Qualcomm Incorporated | Coded MIMO systems with selective channel inversion applied per eigenmode |
US7408978B2 (en) * | 2002-09-09 | 2008-08-05 | Interdigital Technology Corporation | Extended algorithm data estimator |
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US7324429B2 (en) | 2002-10-25 | 2008-01-29 | Qualcomm, Incorporated | Multi-mode terminal in a wireless MIMO system |
US8208364B2 (en) | 2002-10-25 | 2012-06-26 | Qualcomm Incorporated | MIMO system with multiple spatial multiplexing modes |
US8134976B2 (en) | 2002-10-25 | 2012-03-13 | Qualcomm Incorporated | Channel calibration for a time division duplexed communication system |
US7002900B2 (en) | 2002-10-25 | 2006-02-21 | Qualcomm Incorporated | Transmit diversity processing for a multi-antenna communication system |
US8169944B2 (en) | 2002-10-25 | 2012-05-01 | Qualcomm Incorporated | Random access for wireless multiple-access communication systems |
US20040081131A1 (en) | 2002-10-25 | 2004-04-29 | Walton Jay Rod | OFDM communication system with multiple OFDM symbol sizes |
US7042967B2 (en) * | 2003-03-03 | 2006-05-09 | Interdigital Technology Corporation | Reduced complexity sliding window based equalizer |
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US6873596B2 (en) * | 2003-05-13 | 2005-03-29 | Nokia Corporation | Fourier-transform based linear equalization for CDMA downlink |
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US7817754B2 (en) * | 2004-12-01 | 2010-10-19 | Bae Systems Information And Electronic Systems Integration Inc. | M-algorithm with prioritized user ordering |
US7466749B2 (en) | 2005-05-12 | 2008-12-16 | Qualcomm Incorporated | Rate selection with margin sharing |
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US8942321B2 (en) * | 2010-09-22 | 2015-01-27 | Qualcomm Incorporated | Efficient compressed sensing channel estimation for single-carrier communication systems |
US20120127923A1 (en) * | 2010-11-23 | 2012-05-24 | Wanlun Zhao | Method and Apparatus for Enabling a Low Complexity Receiver |
TWI492549B (en) | 2012-10-09 | 2015-07-11 | Realtek Semiconductor Corp | Multi-modes power amplifier circuit, multi-mode wireless transmitting module and method therefor |
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US10404336B1 (en) * | 2017-07-17 | 2019-09-03 | Marvell International Ltd. | Systems and methods for channel correlation based user detection in an uplink multi-user transmission of a multiple-input multiple-output network |
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Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999040698A1 (en) * | 1998-02-09 | 1999-08-12 | Motorola Inc. | Method and apparatus for joint detection of data in a direct sequence spread spectrum communications system |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0696398A1 (en) * | 1994-02-25 | 1996-02-14 | Koninklijke Philips Electronics N.V. | A multiple access digital transmission system and a radio base station and a receiver for use in such a system |
US5790537A (en) * | 1996-05-15 | 1998-08-04 | Mcgill University | Interference suppression in DS-CDMA systems |
US6590889B1 (en) * | 1997-08-11 | 2003-07-08 | Gte Internetworking Incorporated | Data communications system and hybrid time-code multiplexing method |
SE516182C2 (en) * | 1999-02-26 | 2001-11-26 | Ericsson Telefon Ab L M | Receiving different signal format standards in multi-standard radio systems |
US6885654B2 (en) * | 2001-02-06 | 2005-04-26 | Interdigital Technology Corporation | Low complexity data detection using fast fourier transform of channel correlation matrix |
US6625203B2 (en) * | 2001-04-30 | 2003-09-23 | Interdigital Technology Corporation | Fast joint detection |
US6873596B2 (en) * | 2003-05-13 | 2005-03-29 | Nokia Corporation | Fourier-transform based linear equalization for CDMA downlink |
-
2001
- 2001-03-22 US US09/814,346 patent/US6885654B2/en not_active Expired - Lifetime
-
2002
- 2002-01-28 KR KR1020037013881A patent/KR100759297B1/en not_active IP Right Cessation
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- 2002-02-15 US US10/077,509 patent/US6879578B2/en not_active Expired - Lifetime
- 2002-02-15 US US10/077,527 patent/US6904036B2/en not_active Expired - Lifetime
-
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- 2006-03-07 US US11/370,113 patent/US7715305B2/en not_active Expired - Fee Related
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Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999040698A1 (en) * | 1998-02-09 | 1999-08-12 | Motorola Inc. | Method and apparatus for joint detection of data in a direct sequence spread spectrum communications system |
Non-Patent Citations (1)
Title |
---|
BENVENUTO N ET AL: "JOINT DETECTION WITH LOW COMPUTATIONAL COMPLEXITY FOR HYBRID TD-CDMA SYSTEMS" VTC 1999-FALL. IEEE VTS 50TH. VEHICULAR TECHNOLOGY CONFERENCE. GATEWAY TO THE 21ST. CENTURY COMMUNICATIONS VILLAGE. AMSTERDAM, SEPT. 19 - 22, 1999, IEEE VEHICULAR TECHNOLGY CONFERENCE, NEW YORK, NY: IEEE, US, vol. 1 CONF. 50, September 1999 (1999-09), pages 618-622, XP000928922 ISBN: 0-7803-5436-2 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
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EP1843481A1 (en) | 2003-01-10 | 2007-10-10 | Interdigital Technology Corporation | Generalized two-stage data estimation |
US7386033B2 (en) | 2003-01-10 | 2008-06-10 | Interdigital Technology Corporation | Communication system with receivers employing generalized two-stage data estimation |
US7545851B2 (en) | 2003-01-10 | 2009-06-09 | Interdigital Technology Corporation | Communication system with receivers employing generalized two-stage data estimation |
US7796678B2 (en) | 2003-01-10 | 2010-09-14 | Interdigital Technology Corporation | Communication system with receivers employing generalized two-stage data estimation |
US7796680B2 (en) | 2004-02-12 | 2010-09-14 | Nec Corporation | Mobile communication system and wireless apparatus to be used for the same |
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