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    Automatic frequency control in the presence of data
    51.
    发明专利
    Automatic frequency control in the presence of data 未知

    公开(公告)号：IE71666B1

    公开(公告)日：1997-02-26

    申请号：IE402589

    申请日：1989-12-15

    Applicant: MOTOROLA INC

    Inventor： BORTH DAVID EDWARD ,  KEPLER JAMES FRANK MICHAEL

    IPC: H04L27/00 ,  H04L27/14 ,  H04L27/18 ,  H04L27/227 ,  H04L27/22

    Abstract: There is provided a method of and apparatus for Automatic Frequency Control (AFC) in the presence of data. It comprises removing the effects of data modulated onto the carrier (25), detecting the frequency difference between the carrier frequency and the phase of the reference oscillator (30), and adjusting (80) the frequency of the reference oscillator (35) to eliminate the frequency difference ( DELTA ). It is further characterized by digitizing (40) the modulated carrier in quadrature, sampling (20) the modulated carrier in quadrature at a multiple of the modulated bit rate, rotating phases toward arctangent (I/Q)=0 (25/55/60) to remove the effects of quadrature data (I/Q) modulated onto the carrier, detecting (30) the frequency difference ( DELTA ) between the carrier frequency and the frequency of a Voltage Controlled type of reference oscillator (35) with a phase trajectory estimator (45), and establishing and generating the requisite correction voltage ( DELTA ) for a Voltage Controlled type of reference oscillator (VCO) (35) with the phase trajectory estimator (45).

    53.
    发明专利
    未知

    公开(公告)号：FI95524B

    公开(公告)日：1995-10-31

    申请号：FI884940

    申请日：1988-10-26

    Applicant: MOTOROLA INC

    Inventor： LABEDZ GERALD PAUL ,  BORTH DAVID EDWARD

    IPC: H04B7/005 ,  H04B7/01 ,  H04L27/38 ,  H04B7/26 ,  H04L27/22

    Abstract: The method and apparatus for rapid phase acquisition and random radio channel phase error compensation for a TDMA QPSK receiver is disclosed. Received quadrature signals having a known synchronizing sequence transmitted on one of the vectors is correlated to a local replica of the sequence. The output correlation detection signals are held for the duration of the TDMA timeslot and multiplied by the received quadrature signals to produce two pairs of products. The mutually exclusive product pairs are summed to recover data having the random phase error compensated.

    AUTOMATIC FREQUENCY CONTROL IN THE PRESENCE OF DATA.
    54.
    发明专利
    AUTOMATIC FREQUENCY CONTROL IN THE PRESENCE OF DATA. 未知

    公开(公告)号：MY107067A

    公开(公告)日：1995-09-30

    申请号：MYPI19891788

    申请日：1989-12-16

    Applicant: MOTOROLA INC

    Inventor： BORTH DAVID EDWARD ,  KEPLER JAMES FRANK MICHAEL

    IPC: H04L27/14 ,  H04L27/00 ,  H04L27/22 ,  H04L27/18 ,  H04L27/227

    Abstract: THERE IS PROVIDED A METHOD OF AND APPARATUS FOR AUTOMATIC FREQUENCY CONTROL (AFC) IN THE PRESENCE OF DATA. IT COMPRISES REMOVING THE EFFECTS OF DATA MODULATED ONTO THE CARRIER (25), DETECTING THE FREQUENCY DIFFERENCE BETWEEN THE CARRIER FREQUENCY AND THE PHASE OF THE REFERENCE OSCILLATOR (30), AND ADJUSTING (80) THE FREQUENCY OF THE REFERENCE OSCILLATOR (35) TO ELIMINATE THE FREQUENCY DIFFERENCE ( ? ). IT IS FURTHER CHARACTERIZED BY DIGITIZING (40) THE MODULATED CARRIER IN QUADRATURE, SAMPLING (20) THE MODULATED CARRIER IN QUADRATURE AT A MULTIPLE OF THE MODULATED BIT RATE, ROTATING PHASES TOWARD ARCTANGENT (I/Q)=0 (25/55/60) TO REMOVE THE EFFECTS OF QUADRATURE DATA (I/Q) MODULATED ONTO THE CARRIER, DETECTING (30) THE FREQUENCY DIFFERENT ( ? ) BETWEEN THE CARRIER FREQUENCY AND THE FREQUENCY OF A VOLTAGE CONTROLLED TYPE OF REFERENCE OSCILLATOR (35) WITH A PHASE TRAJECTORY ESTIMATOR (45), AND ESTABLISHING AND GENERATING THE REQUISITE CORRECTION VOLTAGE ( ? ) FOR A VOLTAGE CONTROLLED TYPE OF REFERENCE OSCILLATOR (VCO) (35) WITH THE PHASE TRAJECTORY ESTIMATOR (45).

    55.
    发明专利
    未知

    公开(公告)号：AT126640T

    公开(公告)日：1995-09-15

    申请号：AT89121747

    申请日：1989-12-11

    Applicant: MOTOROLA INC

    Inventor： BORTH DAVID EDWARD ,  KEPLER JAMES FRANK MICHAEL

    IPC: H04L27/14 ,  H04L27/00 ,  H04L27/18 ,  H04L27/227 ,  H04L27/22

    Abstract: There is provided a method of and apparatus for Automatic Frequency Control (AFC) in the presence of data. It comprises removing the effects of data modulated onto the carrier (25), detecting the frequency difference between the carrier frequency and the phase of the reference oscillator (30), and adjusting (80) the frequency of the reference oscillator (35) to eliminate the frequency difference ( DELTA ). It is further characterized by digitizing (40) the modulated carrier in quadrature, sampling (20) the modulated carrier in quadrature at a multiple of the modulated bit rate, rotating phases toward arctangent (I/Q)=0 (25/55/60) to remove the effects of quadrature data (I/Q) modulated onto the carrier, detecting (30) the frequency difference ( DELTA ) between the carrier frequency and the frequency of a Voltage Controlled type of reference oscillator (35) with a phase trajectory estimator (45), and establishing and generating the requisite correction voltage ( DELTA ) for a Voltage Controlled type of reference oscillator (VCO) (35) with the phase trajectory estimator (45).

    56.
    发明专利
    未知

    公开(公告)号：PT92433B

    公开(公告)日：1995-09-12

    申请号：PT9243389

    申请日：1989-11-28

    Applicant: MOTOROLA INC

    Inventor： BORTH DAVID EDWARD ,  KEPLER JAMES FRANK MICHAEL ,  CERNY FRANK JOSEPH JR

    IPC: H03G3/20 ,  H04B3/06 ,  H04B7/005 ,  H04B7/26 ,  H04J3/00 ,  H04J3/16 ,  H04L27/18 ,  H04L27/22 ,  H04L27/38 ,  H04B7/00

    Abstract: There is provided a method of digital Automatic Gain Control (AGC) in a receiver having limited dynamic range, particularly for discontinuous signals. The method is characterized by detecting the level of a received and AGC'd discontinuous signal, comparing the level of the AGC'd signal relative to the dynamic range of the receiver, and adjusting the AGC to establish a desired relationship between the AGC'd signal and the dynamic range limitation. There is also provided a method of handoff in a TDMA cellular-type transmission system utilizing this method of AGControl. The method for Automatic Gain Control (AGC) of discontinuous signals in a receiver having limited dynamic range is further characterized by: digitizing (A/D) a received and AGC'd discontinuous signal and converting the digitized samples to a power sample to sense the power of and detect the level of the signal, comparing the level of the AGC'd signal relative to the dynamic range of the receiver; and coarsely-adjusting by either progressively attenuating the signal until it falls within the dynamic range of the receiver or by progressively gain-amplifying the signal until it falls within the limited dynamic range of the receiver and finely-adjusting the AGC of the received signal until optimum use of the full (albeit limited) dynamic range of the signal processing stages is about 6-12 dB below maximum to establish a desired relationship between the AGC'd signal and the dynamic range limitation.

    59.
    发明专利
    未知

    公开(公告)号：MX171680B

    公开(公告)日：1993-11-10

    申请号：MX1815089

    申请日：1989-10-30

    Applicant: MOTOROLA INC

    Inventor： KEPLER JAMES FRANK MICHAEL ,  BORTH DAVID EDWARD ,  CERNY FRANK JOSEPH JR

    IPC: H03G3/20 ,  H04B3/06 ,  H04B7/005 ,  H04B7/26 ,  H04J3/00 ,  H04J3/16 ,  H04L27/18 ,  H04L27/22 ,  H04L27/38 ,  H04L27/14

    Abstract: There is provided a method of digital Automatic Gain Control (AGC) in a receiver having limited dynamic range, particularly for discontinuous signals. The method is characterized by detecting the level of a received and AGC'd discontinuous signal, comparing the level of the AGC'd signal relative to the dynamic range of the receiver, and adjusting the AGC to establish a desired relationship between the AGC'd signal and the dynamic range limitation. There is also provided a method of handoff in a TDMA cellular-type transmission system utilizing this method of AGControl. The method for Automatic Gain Control (AGC) of discontinuous signals in a receiver having limited dynamic range is further characterized by: digitizing (A/D) a received and AGC'd discontinuous signal and converting the digitized samples to a power sample to sense the power of and detect the level of the signal, comparing the level of the AGC'd signal relative to the dynamic range of the receiver; and coarsely-adjusting by either progressively attenuating the signal until it falls within the dynamic range of the receiver or by progressively gain-amplifying the signal until it falls within the limited dynamic range of the receiver and finely-adjusting the AGC of the received signal until optimum use of the full (albeit limited) dynamic range of the signal processing stages is about 6-12 dB below maximum to establish a desired relationship between the AGC'd signal and the dynamic range limitation.

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