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    11.
    发明专利
    未知

    公开(公告)号：BR9902616A

    公开(公告)日：2000-01-18

    申请号：BR9902616

    申请日：1999-06-24

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： HUANG HOWARD C ,  MAILAENDER LAURENCE EUGENE

    IPC: H04B7/06 ,  H04B7/216

    Abstract: A system, a transceiver, and methods for code division multiple access (CDMA) communication. The system includes first and second code division multiple access transceivers. The first code division multiple access transceiver has a plurality antennas disposed to provide transmission via a plurality of paths and the second code division multiple access transceiver has a rake arrangement for processing a plurality of signals received at the rake arrangement with differing delays or other characteristics. A driving arrangement is provided for causing the first code division multiple access transceiver to use a relative few, e.g., one, of the plurality of antennas. When, however, an indication is obtained that an adequate number of resolvable signals are likely not received at the rake arrangement of the second transceiver, a circuit switches the driving arrangement to cause the first transceiver to use more of the plurality of antennas. In one implementation, the second transceiver sends a feedback signal indicating the number of useful signals being received and the first transceiver responds to the feedback signal by selecting and using a desirable number of transmit antennas. In an implementation suitable for a time-division duplexing (TDD) communication system, the first transceiver obtains the indication by inference from the fact that it is not receiving an adequate plurality of resolvable signals from the second transceiver. When the first transceiver obtains the indication, it drives the increased number of antennas either with respective delays or with different codes of the CDMA type.

    12.
    发明专利
    未知

    公开(公告)号：DE69936112T2

    公开(公告)日：2008-01-24

    申请号：DE69936112

    申请日：1999-02-16

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： GANS MICHAEL JAMES ,  MAILAENDER LAURENCE EUGENE ,  YEH YU SHUAN

    IPC: H04B1/707 ,  H04J11/00 ,  H04B7/26 ,  H04J13/00 ,  H04J13/18

    Abstract: A CDMA communication system is disclosed offering a near continuum of data rates up to a maximum rate. The disclosed CDMA communication system increases the data rate variability, without disturbing the orthogonality between users. An increased number of data rates is obtained by time multiplexing the data rates achievable with conventional CDMA systems to provide additional data rates for various multimedia applications. If a user is assigned a specific orthogonal code sequence, such as a Walsh sequence, which permits a maximum data rate, nR, with conventional systems, the user can obtain additional desired data rates up to the maximum rate nR, by time multiplexing the specific orthogonal code set. Desired bit rates are achievable for applications requiring bit rates that are not an integer multiple of the rates provided by conventional techniques. A fundamental rate of R or "fat pipe" rates of powers-of-two multiples of the fundamental rate can be achieved in a conventional manner. A desired rate up to the maximum "fat pipe" rate is achieved by time multiplexing the codes wn_k to achieve rates between R and nR, where wn_k, denotes the first nth of the spread spectrum code wk. The transmitter of the present invention achieves a rate conversion to match the appropriate codeword to the appropriate data rate, by employing buffering and reclocking of the data, with time multiplexing of the orthogonal Walsh codes corresponding to the available lower and upper rates. The rate conversion must be synchronized with the selection of the orthogonal Walsh code (corresponding to the lower and upper rates).

    METHOD AND APPARATUS FOR ACHIEVING DATA RATE VARIABILITY IN ORTHOGONAL SPREAD SPECTRUM COMMUNICATION SYSTEMS
    13.
    发明专利
    METHOD AND APPARATUS FOR ACHIEVING DATA RATE VARIABILITY IN ORTHOGONAL SPREAD SPECTRUM COMMUNICATION SYSTEMS 未知

    公开(公告)号：CA2260522C

    公开(公告)日：2006-09-05

    申请号：CA2260522

    申请日：1999-01-28

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： YEH YU-SHUAN ,  MAILAENDER LAURENCE EUGENE ,  GANS MICHAEL JAMES

    IPC: H04B1/69 ,  H04B1/707 ,  H04B1/18 ,  H04J11/00 ,  H04J13/00 ,  H04J13/18

    Abstract: A CDMA communication system is disclosed offering a near continuum of data rates up to a maximum rate. The disclosed CDMA communication system increases the data rate variability, without disturbing the orthogonality between users. An increased number of data rates is obtained by time multiplexing the data rates achievable with conventional CDMA systems to provide additional data rates f or various multimedia applications. If a user is assigned a specific orthogonal code sequence, such as a Walsh sequence, which permits a maximum data rate, n R, with conventional systems, the user can obtain additional desired data rates up t o the maximum rate n R, by time multiplexing the specific orthogonal code set. Desired bit rates are achievable for applications requiring bit rates that are not an integer multiple of the rates provided by conventional techniques. A fundamental rate of R or "fat pipe" rates of powers-of-two multiples of the fundamental rate can be achiev ed in a conventional manner. A desired rate up to the maximum "fat pipe" rate is achieved by time multiplexing the codes w k n to achieve rates between R and nR, wher e w k n, denotes the first nth of the spread spectrum code w k. The transmitter of th e present invention achieves a rate conversion to match the appropriate codeword to th e appropriate data rate, by employing buffering and reclocking of the data, wi th time multiplexing of the orthogonal Walsh codes corresponding to the available lower and upper rates. The rate conversion must be synchronized with the selection of the orthogonal Walsh code (corresponding to the lower and upper rates).

    14.
    发明专利
    未知

    公开(公告)号：DE60022941D1

    公开(公告)日：2006-02-16

    申请号：DE60022941

    申请日：2000-05-09

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： ANDERLIND ERIK EINAR ,  MAILAENDER LAURENCE EUGENE

    IPC: G06F13/00 ,  H03M7/40 ,  H04J3/06 ,  H04L1/00 ,  H04L7/00 ,  H04L7/04

    Abstract: In order to transmit variable length encoded data in low signal to noise ratio environments, a first data pattern is added to a beginning portion of encoded data to signify a beginning of the encoded data. Further, a second data pattern is added to end portion of the encoded data to signify and end of the encoded data. Additionally, since the encoded data may naturally include the second data pattern and thereby mistakenly indicate an end of the encoded data, the encoded data is first checked for such a pattern. If the pattern is found within the encoded data, a new pattern is substituted therefore. In order to counter errors, patterns similar to the first data pattern are also substituted with new patterns. As such, a variable length encoded data can be transmitted in a low signal to noise ratio environment, and can thereafter be easily decoded.

    DETECTORS FOR CDMA SYSTEMS
    15.
    发明专利
    DETECTORS FOR CDMA SYSTEMS 未知

    公开(公告)号：CA2279471A1

    公开(公告)日：2000-02-04

    申请号：CA2279471

    申请日：1999-07-30

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： MAILAENDER LAURENCE EUGENE ,  HUANG HOWARD C ,  PAPADIAS CONSTANTINOS BASIL

    IPC: H04B1/10 ,  H04B1/7093 ,  H04B1/7103 ,  H04B1/7105 ,  H04B1/7115 ,  H04B1/707 ,  H04B1/16

    Abstract: Linear space-time multiuser detectors are described that combine array processing, rake detection, and multiuser detection and that satisfy a minimum mean-squared error criteria. Both embodiments can be implemented adaptively so as to account for unknown sources of interference. The adaptive implementation of the first embodiment of a linear space-time detector requires explicit estimates of the channel coefficients. On the other hand, the adaptive implementation of the second embodiment does not require these estimates since they can be adaptively obtained. Both of these detectors provide significant performance advantages over single-user space-time detectors and over multiuser detectors which do not account for CDMA interference from unknown sources.

    METHOD AND APPARATUS FOR ACHIEVING DATA RATE VARIABILITY IN ORTHOGONAL SPREAD SPECTRUM COMMUNICATION SYSTEMS
    16.
    发明专利
    METHOD AND APPARATUS FOR ACHIEVING DATA RATE VARIABILITY IN ORTHOGONAL SPREAD SPECTRUM COMMUNICATION SYSTEMS 未知

    公开(公告)号：CA2260522A1

    公开(公告)日：1999-08-27

    申请号：CA2260522

    申请日：1999-01-28

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： GANS MICHAEL JAMES ,  YEH YU-SHUAN ,  MAILAENDER LAURENCE EUGENE

    IPC: H04B1/707 ,  H04J11/00 ,  H04J13/00 ,  H04J13/18 ,  H04B1/69 ,  H04B1/18

    Abstract: A CDMA communication system is disclosed offering a near continuum of data rates up to a maximum rate. The disclosed CDMA communication system increases the data rate variability, without disturbing the orthogonality between users. An increased number of data rates is obtained by time multiplexing the data rates achievable with conventional CDMA systems to provide additional data rates for various multimedia applications. If a user is assigned a specific orthogonal code sequence, such as a Walsh sequence, which permits a maximum data rate, nR, with conventional systems, the user can obtain additional desired data rates up to the maximum rate nR, by time multiplexing the specific orthogonal code set. Desired bit rates are achievable for applications requiring bit rates that are not an integer multiple of the rates provided by conventional techniques. A fundamental rate of R or "fat pipe" rates of powers-of-two multiples of the fundamental rate can be achieved in a conventional manner. A desired rate up to the maximum "fat pipe" rate is achieved by time multiplexing the codes w k n to achieve rates between R and nR, where w k n, denotes the first nth of the spread spectrum code w k. The transmitter of the present invention achieves a rate conversion to match the appropriate codeword to the appropriate data rate, by employing buffering and reclocking of the data, with time multiplexing of the orthogonal Walsh codes corresponding to the available lower and upper rates. The rate conversion must be synchronized with the selection of the orthogonal Walsh code (corresponding to the lower and upper rates).

    17.
    发明专利
    未知

    公开(公告)号：DE69936112D1

    公开(公告)日：2007-07-05

    申请号：DE69936112

    申请日：1999-02-16

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： GANS MICHAEL JAMES ,  MAILAENDER LAURENCE EUGENE ,  YEH YU SHUAN

    IPC: H04B1/707 ,  H04J11/00 ,  H04B7/26 ,  H04J13/00 ,  H04J13/18

    Abstract: A CDMA communication system is disclosed offering a near continuum of data rates up to a maximum rate. The disclosed CDMA communication system increases the data rate variability, without disturbing the orthogonality between users. An increased number of data rates is obtained by time multiplexing the data rates achievable with conventional CDMA systems to provide additional data rates for various multimedia applications. If a user is assigned a specific orthogonal code sequence, such as a Walsh sequence, which permits a maximum data rate, nR, with conventional systems, the user can obtain additional desired data rates up to the maximum rate nR, by time multiplexing the specific orthogonal code set. Desired bit rates are achievable for applications requiring bit rates that are not an integer multiple of the rates provided by conventional techniques. A fundamental rate of R or "fat pipe" rates of powers-of-two multiples of the fundamental rate can be achieved in a conventional manner. A desired rate up to the maximum "fat pipe" rate is achieved by time multiplexing the codes wn_k to achieve rates between R and nR, where wn_k, denotes the first nth of the spread spectrum code wk. The transmitter of the present invention achieves a rate conversion to match the appropriate codeword to the appropriate data rate, by employing buffering and reclocking of the data, with time multiplexing of the orthogonal Walsh codes corresponding to the available lower and upper rates. The rate conversion must be synchronized with the selection of the orthogonal Walsh code (corresponding to the lower and upper rates).

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