公开(公告)号：SE9502703D0

公开(公告)日：1995-07-27

申请号：SE9502703

申请日：1995-07-27

Applicant: MOTOROLA INC

Inventor： LOVE ROBERT TRISTAN ,  STEWART KENNETH A ,  RAPALA BRYAN

IPC: H04L27/22 ,  H04B1/707 ,  H04L27/227

Abstract: The present invention provides a downconverter method and apparatus for downconverting a multiphase modulated signal. The downconverter can be implemented in a multi-phase receiver such as a quadrature receiver. An analog-to-digital converter (103) converts an intermediate frequency signal to a digital signal at a sampling rate. A Hilbert transformation filter (104) and a delay element (105) connected in parallel provide respective passband quadrature and in-phase components of the digital signal. A digital translator (107) alters the passband quadrature and in-phase components based on a predetermined pattern to provide a baseband quadrature signal and a baseband in-phase signal. The digital translator (107) can be a pseudorandom sequence demodulator for demodulating a code division multiple access (CDMA) signal. Various types of DC estimation can also be provided in addition to automatic gain control.

公开(公告)号：SE9502703L

公开(公告)日：1995-10-02

申请号：SE9502703

申请日：1995-07-27

Applicant: MOTOROLA INC

Inventor： LOVE ROBERT TRISTAN ,  STEWART KENNETH A ,  RAPALA BRYAN

IPC: H04B1/707 ,  H04L27/227 ,  H04L27/22 ,  H04L27/38

Abstract: The present invention provides a downconverter method and apparatus for downconverting a multiphase modulated signal. The downconverter can be implemented in a multi-phase receiver such as a quadrature receiver. An analog-to-digital converter (103) converts an intermediate frequency signal to a digital signal at a sampling rate. A Hilbert transformation filter (104) and a delay element (105) connected in parallel provide respective passband quadrature and in-phase components of the digital signal. A digital translator (107) alters the passband quadrature and in-phase components based on a predetermined pattern to provide a baseband quadrature signal and a baseband in-phase signal. The digital translator (107) can be a pseudorandom sequence demodulator for demodulating a code division multiple access (CDMA) signal. Various types of DC estimation can also be provided in addition to automatic gain control.

公开(公告)号：CA2153682C

公开(公告)日：1999-03-23

申请号：CA2153682

申请日：1994-10-25

Applicant: MOTOROLA INC

Inventor： RAPALA BRYAN ,  LOVE ROBERT TRISTAN ,  STEWART KENNETH A

IPC: H04L27/22 ,  H04B1/707 ,  H04L27/227 ,  H04L27/00

Abstract: The present invention provides a downconverter method and apparatus for downconverting a multiphase modulated signal. The downconverter can be implemented in a multi-phase receiver such as a quadrature receiver. An analogto-digital converter (103) converts an intermediate frequency signal to a digital signal at a sampling rate. A Hilbert transformation filter (104) and a delay element (105) connected in parallel provide respective passband quadrature and in-phase components of the digital signal. A digital translator (107) alters the passband quadrature and in-phase components based on a predetermined pattern to provide a baseband quadrature signal and a baseband in-phase signal. The digital translator (107) can be a pseudorandom sequence demodulator for demodulating a code division multiple access (CDMA) signal. Various types of DC estimation can also be provided in addition to automatic gain control.

公开(公告)号：CA2153682A1

公开(公告)日：1995-06-08

申请号：CA2153682

申请日：1994-10-25

Applicant: MOTOROLA INC

Inventor： LOVE ROBERT TRISTAN ,  RAPALA BRYAN ,  STEWART KENNETH A

IPC: H04L27/22 ,  H04B1/707 ,  H04L27/227 ,  H04L27/00

Abstract: The present invention provides a downconverter method and apparatus for downconverting a multiphase modulated signal. The downconverter can be implemented in a multi-phase receiver such as a quadrature receiver. An analog-to-digital converter (103) converts an intermediate frequency signal to a digital signal at a sampling rate. A Hilbert transformation filter (104) and a delay element (105) connected in parallel provide respective passband quadrature and in-phase components of the digital signal. A digital translator (107) alters the passband quadrature and in-phase components based on a predetermined pattern to provide a baseband quadrature signal and a baseband in-phase signal. The digital translator (107) can be a pseudorandom sequence demodulator for demodulating a code division multiple access (CDMA) signal. Various types of DC estimation can also be provided in addition to automatic gain control.

公开(公告)号：MX9400805A

公开(公告)日：1994-08-31

申请号：MX9400805

申请日：1994-01-31

Applicant: MOTOROLA INC

Inventor： LOVE ROBERT TRISTAN

IPC: H03M13/23 ,  H03H21/00 ,  H04B7/005 ,  H04L7/04 ,  H04L7/08 ,  H04L25/02 ,  H04L25/03 ,  H04B3/00

Abstract: A method is provided of updating an estimated channel impulse response of a maximum likelihood sequence estimator within a radio receiver (12 and 13). The method includes the steps of computing a rate of change of a channel impulse response from a current estimated channel impulse response and a previous estimated channel impulse response, selecting an update step size as a function of the rate of change of the estimated channel impulse response, and updating the estimated channel impulse response of the maximum likelihood sequence estimator based upon the selected step size. Apparatus is also provided of practicing the method in receiving and decoding a signal.

公开(公告)号：EP0632947A4

公开(公告)日：1997-04-16

申请号：EP94903307

申请日：1993-11-26

Applicant: MOTOROLA INC

Inventor： LOVE ROBERT TRISTAN ,  LABEDZ GERALD PAUL ,  BAUM KEVIN LYNN

IPC: H04L27/00 ,  H03H15/00 ,  H03H17/00 ,  H03H21/00 ,  H03M13/23 ,  H03M13/41 ,  H04B1/10 ,  H04B3/04 ,  H04B7/005 ,  H04L1/00 ,  H04L7/00 ,  H04L25/03 ,  H04L27/06 ,  H03M13/12

CPC classification number: H03M13/6331 ,  H03M13/41 ,  H04L25/03178 ,  H04L25/03292 ,  H04L2025/03547

Abstract: An apparatus is provided for maximum likelihood sequence estimation. The apparatus includes a first maximum likelihood sequence estimator (44) in a signal path for flat fading and an at least second maximum likelihood sequence estimator (45) in other signal path for other than fading. The apparatus further includes a switch (47) for selecting the signal path with a least relative magnitude means square error.