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    23.
    发明专利
    未知

    公开(公告)号：DE69932118D1

    公开(公告)日：2006-08-10

    申请号：DE69932118

    申请日：1999-04-27

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： LUSCHI CARLO ,  SANDELL MAGNUS ,  MUJTABA SYED AON ,  STRAUCH PAUL EDWARD ,  TEN BRINK STEPHAN DIPL ING ,  YAN RAN-HONG

    IPC: H04L25/02 ,  H04L27/01

    Abstract: A method of estimating channel impulse response in a signal transmitted over a channel in a communication system is described. The channel estimator obtains a priori knowledge about the transmitted signal, and then uses the transmitted signal and the a priori knowledge to choose an estimate of channel impulse response which minimizes the expected distance between the transmitted signal and a reconstructed signal. The expected distance that is minimized is a cost function, represented by E{∥r-Bh∥2r}. By using soft decision feedback, the invention minimizes erroneous decision feedback which can cause error propagation. The decisions are usually in the form of log likelihood ratios (LLR).

    SIGNAL ENCODING FOR TRANSMISSION OF MULTIPLE DIGITAL SIGNALSOVER SINGLE PHYSICAL MEDIUM
    24.
    发明专利
    SIGNAL ENCODING FOR TRANSMISSION OF MULTIPLE DIGITAL SIGNALSOVER SINGLE PHYSICAL MEDIUM 未知

    公开(公告)号：CA2314400C

    公开(公告)日：2004-05-25

    申请号：CA2314400

    申请日：2000-07-21

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： MUJTABA SYED AON ,  GABARA THADDEUS JOHN

    IPC: H03M5/12 ,  H03M5/16 ,  H04B14/00 ,  H04J1/00 ,  H04J11/00 ,  H04L5/02 ,  H04L25/49

    Abstract: Two or more digital signals are encoded using two or more respective li ne codes. The line codes are chosen in conjunction with the data rates of the digital signals such that the encoded signals are substantially orthogonal to each other in the frequency domain. As such, the two or more encoded signals may be combin ed and transmitted via a single physical medium with little or no interference. A transmitter for encoding and transmitting the digital signals contains line coders for encoding the digital signals and a combiner for combining the encoded signal s for transmission via a single physical medium. A receiver for receiving and decoding the combined encoded signal contains filters for extracting the individual encoded signals and line decoders for decoding the individual encoded signals to generate the original digital data signals.

    SIGNAL ENCODING FOR TRANSMISSION OF MULTIPLE DIGITAL SIGNALS OVER SINGLE PHYSICAL MEDIUM
    26.
    发明专利
    SIGNAL ENCODING FOR TRANSMISSION OF MULTIPLE DIGITAL SIGNALS OVER SINGLE PHYSICAL MEDIUM 未知

    公开(公告)号：CA2314400A1

    公开(公告)日：2001-01-29

    申请号：CA2314400

    申请日：2000-07-21

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： GABARA THADDEUS JOHN ,  MUJTABA SYED AON

    IPC: H03M5/12 ,  H03M5/16 ,  H04B14/00 ,  H04J1/00 ,  H04J11/00 ,  H04L5/02 ,  H04L25/49

    Abstract: Two or more digital signals are encoded using two or more respective li ne codes. The line codes are chosen in conjunction with the data rates of the digital signals such that the encoded signals are substantially orthogonal to each other in the frequency domain. As such, the two or more encoded signals may be combin ed and transmitted via a single physical medium with little or no interference. A transmitter for encoding and transmitting the digital signals contains line coders for encoding the digital signals and a combiner for combining the encoded signal s for transmission via a single physical medium. A receiver for receiving and decoding the combined encoded signal contains filters for extracting the individual encoded signals and line decoders for decoding the individual encoded signals to generate the original digital data signals.

    27.
    发明专利
    未知

    公开(公告)号：DE69934866T2

    公开(公告)日：2007-07-05

    申请号：DE69934866

    申请日：1999-11-16

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： MUJTABA SYED AON

    IPC: H04J11/00 ,  H04L5/14 ,  H04J99/00 ,  H04L5/02 ,  H04Q7/20 ,  H04Q7/36 ,  H04W88/18

    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.

    METHODS AND APPARATUS FOR WIRELESS COMMUNICATION USING CODE DIVISION DUPLEX TIME-SLOTTED CDMA
    28.
    发明专利
    METHODS AND APPARATUS FOR WIRELESS COMMUNICATION USING CODE DIVISION DUPLEX TIME-SLOTTED CDMA 未知

    公开(公告)号：CA2286417C

    公开(公告)日：2006-01-03

    申请号：CA2286417

    申请日：1999-10-18

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： MUJTABA SYED AON

    IPC: H04Q7/36 ,  H04B7/216 ,  H04B7/26 ,  H04J11/00 ,  H04L5/02 ,  H04L5/14 ,  H04Q7/20 ,  H04W88/18

    Abstract: Methods and apparatus for wireless communication in systems such as omni-be am 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 a re 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 covera ge 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.

    CONTROL TECHNIQUE FOR A COMMUNICATION SYSTEM
    30.
    发明专利
    CONTROL TECHNIQUE FOR A COMMUNICATION SYSTEM 未知

    公开(公告)号：CA2342411A1

    公开(公告)日：2001-11-24

    申请号：CA2342411

    申请日：2001-03-29

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： MUJTABA SYED AON ,  GABARA THADDEUS JOHN

    IPC: H01Q3/26 ,  H04B7/26 ,  H04W16/32 ,  H04W88/08 ,  H04Q7/30 ,  H04Q7/36

    Abstract: A control technique for a communication system in which a microcell base station is co-located with a macrocell base station. The microcell base station trac ks hot spots as they move within the macrocell. The microcell base station may utilize a two - dimensional (2-D) antenna array, which is co-located with the macro cell antenna. The two-dimensional antenna is steerable in both the horizontal and vertical directions. The size of the microcell coverage area depends upon the distance from the cell site antenna as well as the dimensionality of the array, which determines the angular spread of the beam. Filter tap weights may be adjusted to point the beam to any desired location in the macrocell. The orthogonality between the macrocell and the microcell may be obtained either in the frequency domain or in the code domain, depending upon the system in which it is implemented.

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