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公开(公告)号：JP2000165940A
公开(公告)日：2000-06-16
申请号：JP33338599
申请日：1999-11-24
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MUJTABA SYED AON
IPC: H04B7/26 , H04J11/00 , H04L5/02 , H04L5/14 , H04Q7/20 , H04Q7/36 , H04W88/18 , H04J13/00 , H04Q7/10
Abstract: PROBLEM TO BE SOLVED: To improve the performance of a radio communication system by communicating information through at least either of an up link or a down link between plural subscribers' devices and a base station and dividing communication on the up link and communication on the down link by using code division duplexing technique. SOLUTION: A code division duplexing(CDD) mechanism uses different codes for an up link part and a down link part. The up link is shown by N, N-1, etc., and the down link is shown by 1, 2, etc. The boundary between an up link code and a down link code changes, and capacities allocated to the up and down links fluctuate in accordance with the fluctuation of demand. The boundary fluctuates in every time slot or in every group of the prescribed number of time slots. As for the up and down links, it is also possible to increase one and to reduce the other by reallocating the up link code and the down link code.
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公开(公告)号：JP2000183848A
公开(公告)日：2000-06-30
申请号：JP33338499
申请日：1999-11-24
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MUJTABA SYED AON
Abstract: PROBLEM TO BE SOLVED: To realize a wireless communication by a fixed wireless loop(FWL). SOLUTION: In this CDMA wireless communication system having code- division duplex(CDD) time slot constitution, communications over an up link are discriminated from communications on a down link by using code division duplex technology and communications with a different subscriber in a cell is discriminated by using code division multiple access technology, e.g. time- slotted CDMA technology. This code division duplex technology is realized by, for example, assigning a 1st subset in a group of codes to the up link and a 2nd subset to the down link.
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公开(公告)号：JP2000059273A
公开(公告)日：2000-02-25
申请号：JP12016699
申请日：1999-04-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LUSCHI CARLO , MUJTABA SYED AON , SANDELL MAGNUS , STRAUCHI PAUL EDWARD , YAN RAN-HONG , TEN BRINK STEPHAN
Abstract: PROBLEM TO BE SOLVED: To obtain an equalizer which has the effect of propagation reduced for the estimation of the channel impulse response of a transmit signal. SOLUTION: The channel impulse response of a signal transmitted over a channel of a communication system is estimated. Previous information regarding a transmit signal is obtained first. Then an estimated value of channel impulse response which minimizes an expected value of the distance between the transmit signal and a reconstituted signal is selected by using the transmit signal and previous information. For example, the minimized distance expected value is a cost function and represented, specially, as E ||r-Bh||2|r}. Here, (r) is a received signal, (h) is a vector representing the channel, and B is a matrix including transmission bits as components. Further, the previous information is obtained through data estimation which is performed for the transmit signal and obtained, specially, by a channel decoder 14. Further, an estimated value by, for example, channel observation is selected.
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公开(公告)号：JPH11313037A
公开(公告)日：1999-11-09
申请号：JP1568299
申请日：1999-01-25
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LUSCHI CARLO , MUJTABA SYED AON , SANDELL MAGNUS , STRAUCHI PAUL EDWARD , TEN BRINK STEPHAN , YAN RAN-HONG
Abstract: PROBLEM TO BE SOLVED: To provide a device for satisfying the quality of respective different target services by changing the number of times of encoding step repetition for each user. SOLUTION: Concerning the device composed of a signal processing unit 40 and a decoding resource for repeating a process for repeatedly decoding a signal at least once so as to repeatedly decode the signal, the said repeated decoding resource is arranged inside a central pool 41 and when the repeated decoding process is required, this resource is allocated to the signal processing unit 40.
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公开(公告)号：JPH11239189A
公开(公告)日：1999-08-31
申请号：JP32363698
申请日：1998-11-13
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MUJTABA SYED AON
Abstract: PROBLEM TO BE SOLVED: To provide a technique for allowing modulation of signals by performing modulation to cosine carrier wave signals for the Hilbert transformation of common-mode data signals and quadrature phase data signals and performing modulation to sine carrier wave signals for the Hilbert transformation of the quadrature phase data signals and the common-mode data signals. SOLUTION: An SSB-QPSK transmitter 60 is provided with interpolation devices 62 and 64 for interpolating respective data brought by input signals X[n] and Y[n] by zero. Interpolated signals X[n] are separated into two parts, one part is delayed by a delay element 66 and the other part is Hilbert transformed in a Hilbert filter 68. The delayed version of X[n] from the delay element 66 is supplied to a signal coupler 70 and the Hilbert transformation of X[n] is supplied to another signal coupler 72. The delay of the delay element 66 is selected so as to match the delay by the Hilbert filter 68.
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Patent Agency Ranking
公开(公告)号：JP2003092536A
公开(公告)日：2003-03-28
申请号：JP2002187012
申请日：2002-06-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MUJTABA SYED AON
Abstract: PROBLEM TO BE SOLVED: To provide a decoder which can be packaged with high area efficiency and little complexity at a low cost by various application including an application to utilize the code of a great restrict length in a wireless base station receiver or the like. SOLUTION: This decoder has a branch metric calculator 88, an ACS engine 90 and a traceback unit 92. The branch metric calculator 88 computes branch metrics for transitions in a trellis representative of a convolutional code used to generate the symbols. The branch metrics are computed from an offset binary representation of the symbols using an inverse likelihood function, such that a strong match between a given received symbol and a possible codeword of the convolutional code results in a small branch metric, while a weaker match between a given received symbol and a possible codeword results in a larger branch metric. The corresponding path metrics therefore grow at a smaller rate.
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公开(公告)号：JP2001069120A
公开(公告)日：2001-03-16
申请号：JP2000226696
申请日：2000-07-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor： GABARA THADDEUS JOHN , MUJTABA SYED AON
Abstract: PROBLEM TO BE SOLVED: To provide signal encoding for transmitting plural digital signals through a single physical medium. SOLUTION: Digital signals more than two are encoded using respective line codes more than two. The line code is selected from combination with the data rate of the digital signal so that encoded signals can be mutually practically orthogonal in a frequency domain. Then, encoded signals more than two can be combined and transmitted almost or completely without interference. A transmitter 602 for encoding and transmitting digital signals is provided with a coder for encoding digital signals and a combiner for combining the signals encoded for transmission through a single physical medium. A receiver 620 for receiving and decoding the combined and encoded signals is provided with a filter for extracting each of encoded signals and a line decoder for decoding each of encoded signals for generating original digital data signals.
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公开(公告)号：JP2000165939A
公开(公告)日：2000-06-16
申请号：JP33338399
申请日：1999-11-24
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MUJTABA SYED AON
IPC: H04J11/00 , H04J99/00 , H04L5/02 , H04L5/14 , H04Q7/20 , H04Q7/36 , H04W88/18 , H04J13/00 , H04Q7/10
Abstract: PROBLEM TO BE SOLVED: To improve the performance of a radio communication system by communicating information through at least either of an up link or a down link between plural subscribers' devices and a base station and dividing communication on the up link and communication on the down link by using orthogonal frequency division multiplexing technique. SOLUTION: The duplication between a down link part 102 and an up link part 104 is performed by using an orthogonal frequency tone in a frequency domain. Thus, it is possible to change an up link capacity and a down link capacity. The parts 102 and 104 are distinguished by a variable boundary 106 in the frequency domain. M pieces of orthogonal frequency tones 110 exist in all within a prescribed band. Orthogonal frequency tones 1 to k are allocated to the part 104 and orthogonal frequency tones k+1 to M are allocated to the part 102. Thus, a frequency is appropriately allocated between the up and down links in accordance with the fluctuation of demand.
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公开(公告)号：DE69941553D1
公开(公告)日：2009-12-03
申请号：DE69941553
申请日：1999-06-15
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MUJTABA SYED AON
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公开(公告)号：DE69934866D1
公开(公告)日：2007-03-08
申请号：DE69934866
申请日：1999-11-16
Applicant: LUCENT TECHNOLOGIES INC
Inventor： MUJTABA SYED AON
Abstract: Methods and apparatus for wireless communication in systems such as omni-beam and narrow-beam fixed wireless loop (FWL) systems. In a first technique in accordance with the invention, referred to as code division duplex (CDD) time-slotted CDMA, uplink and downlink portions of the system are separated using code division duplexing, while the users within a given cell are also separated using codes, e.g., using time-slotted CDMA. In a second technique in accordance with the invention, referred to as time division duplex (TDD) time-slotted CDMA, uplink and downlink portions of the system are separated using time division duplexing, e.g., time slots, while the users in a given cell are separated using codes, e.g., time-slotted CDMA. Both the CDD and TDD techniques may make use of an electronically-steered beam which is designed to provide simultaneous coverage within a given cell for two or more users separated by codes. In a third technique in accordance with the invention, referred to as orthogonal frequency division multiplexing (OFDM), uplink and downlink portions of the system are separated in frequency, while the users are, e.g., also separated in frequency.
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