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    DECODERLESS BIT-ERROR-RATE ESTIMATION FOR CONVOLUTIONALLY ENCODED TRANSMISSIONS IN WIRELESS SYSTEMS
    22.
    发明专利
    DECODERLESS BIT-ERROR-RATE ESTIMATION FOR CONVOLUTIONALLY ENCODED TRANSMISSIONS IN WIRELESS SYSTEMS 未知

    公开(公告)号：CA2369197A1

    公开(公告)日：2002-08-20

    申请号：CA2369197

    申请日：2002-01-23

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： REGE KIRAN M ,  MONOGIOUDIS PANTELIS

    IPC: H03M13/01 ,  H04L1/00 ,  H04L1/20 ,  H04B17/00 ,  H04Q7/34

    Abstract: In a UMTS (universal mobile telecommunications system) based system, a wireless receiver implements "effective signal-to-noise (E b/N o) based BER estimation." In particular, the wireless receiver comprises a rake receiver, a processor and memory. The rake receiver processes a received signal and provides signa l- to- noise ratio values for each slot of each received frame of the received signal. The processor converts these signal-to-noise ratio values for each received fram e into an effective signal-to-noise ratio value for the received signal. The processor then uses the effective signal-to-noise ratio value as a pointer, or index, into a loo k- up table (stored in the memory) and retrieves a BER estimate therefrom.

    Preamble detector for a CDMA receiver
    23.
    发明专利
    Preamble detector for a CDMA receiver 未知

    公开(公告)号：AU748875B2

    公开(公告)日：2002-06-13

    申请号：AU7208800

    申请日：2000-12-07

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： BHATOOLAUL DAVID LAHIRI ,  MONOGIOUDIS PANTELIS

    IPC: H04B1/707 ,  H04B7/26 ,  H04J13/02 ,  H04B7/216 ,  H04L27/38

    Abstract: A receiver in a code-division, multiple-access (CDMA) communication system employs a preamble detector for random access channels (e.g., RACHs). RACHs may use orthogonal Gold code (OGC) sequences for preamble signature sequences and/or spreading of the preamble signature sequence with OGC sequences. A preamble detector may employ a fast orthogonal Gold transform (FOGT) for both despreading (e.g., correlation with code numbers C1,...,C256)) and for generating a decision statistic for detecting (identifying) the signature sequence used in the preamble. The spread signal of the RACH is applied to a code matched filter (CMF) matched to the spreading OGC sequence and the output signal of the CMF is sampled at the symbol rate. A fast Hadamaard transform (FHT) is applied to the sampled output of the CMF, and the exemplary 16th order code-words of the FHT match the 16 Walsh signature sequences employed to distinguish user channels transmitted by user equipment. A fast OGC transform (FOGT) may be applied to the sampled output of the CMF if OGC sequences are used as signature sequences. The signals generated by the FHT may be split into two branches for processing: a reference branch and a data branch. The reference branch processes the FHT generated signals to estimate channel response characteristics, provide a de-rotation signal, and perform frequency acquisition if required. For the reference branch, the squared magnitude of each complex FHT vector signal of length 16 is calculated and the maximum value is set as index i, where i ELEMENT ä1,.....16ü. The maximum index i is employed as a preliminary, non-coherent decision statistic corresponding to the index value of the Walsh signature sequence used for the spread signal of the access channel. The index i of the reference branch may then be used by: 1) a Walsh generator to reproduce the Walsh (BPSK) signature sequence; 2) a selector to select one of the 16 FHT output signals to estimate channel response characteristics; and 3) as a non-coherent decision statistic for subsequent processing by the detector.

    25.
    发明专利
    未知

    公开(公告)号：BR0005815A

    公开(公告)日：2001-07-24

    申请号：BR0005815

    申请日：2000-12-08

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： BHATOOLAUL DAVID LAHIRI ,  MONOGIOUDIS PANTELIS

    IPC: H04B1/707 ,  H04B7/26 ,  H03D1/00 ,  H04B7/216

    Abstract: A receiver in a code-division, multiple-access (CDMA) communication system employs a preamble detector for random access channels (e.g., RACHs). RACHs may use orthogonal Gold code (OGC) sequences for preamble signature sequences and/or spreading of the preamble signature sequence with OGC sequences. A preamble detector may employ a fast orthogonal Gold transform (FOGT) for both despreading (e.g., correlation with code numbers C1,...,C256)) and for generating a decision statistic for detecting (identifying) the signature sequence used in the preamble. The spread signal of the RACH is applied to a code matched filter (CMF) matched to the spreading OGC sequence and the output signal of the CMF is sampled at the symbol rate. A fast Hadamaard transform (FHT) is applied to the sampled output of the CMF, and the exemplary 16th order code-words of the FHT match the 16 Walsh signature sequences employed to distinguish user channels transmitted by user equipment. A fast OGC transform (FOGT) may be applied to the sampled output of the CMF if OGC sequences are used as signature sequences. The signals generated by the FHT may be split into two branches for processing: a reference branch and a data branch. The reference branch processes the FHT generated signals to estimate channel response characteristics, provide a de-rotation signal, and perform frequency acquisition if required. For the reference branch, the squared magnitude of each complex FHT vector signal of length 16 is calculated and the maximum value is set as index i, where i ELEMENT ä1,.....16ü. The maximum index i is employed as a preliminary, non-coherent decision statistic corresponding to the index value of the Walsh signature sequence used for the spread signal of the access channel. The index i of the reference branch may then be used by: 1) a Walsh generator to reproduce the Walsh (BPSK) signature sequence; 2) a selector to select one of the 16 FHT output signals to estimate channel response characteristics; and 3) as a non-coherent decision statistic for subsequent processing by the detector.

    FHT-BASED RACH PREAMBLE DETECTION
    26.
    发明专利
    FHT-BASED RACH PREAMBLE DETECTION 未知

    公开(公告)号：CA2325649A1

    公开(公告)日：2001-06-15

    申请号：CA2325649

    申请日：2000-11-10

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： BHATOOLAUL DAVID LAHIRI ,  MONOGIOUDIS PANTELIS

    IPC: H04B1/707 ,  H04B7/26 ,  H04B1/69

    Abstract: A receiver in a code-division, multiple-access (CDMA) communication system employs a preamble detector for random access channels (e.g., RACHs). RACHs may use orthogonal Gold code (OGC) sequences for preamble signature sequence s and/or spreading of the preamble signature sequence with OGC sequences. A preamble detector may employ a fast orthogonal Gold transform (FOGT) for both despreading (e.g ., correlation with code numbers C1,...,C256)) and for generating a decision statistic for detecting (identifying) the signature sequence used in the preamble. The spread signal of the RACH is applied to a code matched filter (CMF) matched to the spreading OGC sequence and the output signal of the CMF is sampled at the symbol rate. A fast Hadamaard transform (FHT) is applied to the sampled output of the CMF, and t he exemplary 16th order code-words of the FHT match the 16 Walsh signature sequences employed to distinguish user channels transmitted by user equipment. A fast OGC transform (FOGT) may be applied to the sampled output of the CMF if OGC sequences are used as signature sequences. The signals generated by the FHT may be split into two branches for processing: a reference branch and a data branch. The reference branch processes the FHT generated signals to estimate channel response characteristics, provide a de-rotation signal, and perform frequency acquisition if required. For the reference branch, the squared magnitude of each complex FHT vector signal of length 16 is calculated and the maximum value is set as index i, where i , { 1,.....16}. The maximum index i is employed as a preliminary, non-coherent decision statistic corresponding to the index value of the Walsh signature sequence used for the spread signal of the access channel. The ind ex i of the reference branch may then be used by: 1 ) a Walsh generator to reproduce the Walsh (BPSK) signature sequence; 2) a selector to select one of the 16 FHT output signals to estimate channel response characteristics; and 3) as a non-coherent decision statisti c for subsequent processing by the detector.

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