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公开(公告)号：CA2000785C
公开(公告)日：1994-10-25
申请号：CA2000785
申请日：1989-10-16
Applicant: MOTOROLA INC
Inventor： KEPLER JAMES F M , BORTH DAVID E , CERNY FRANK J JR
IPC: H03G3/20 , H04B3/06 , H04B7/005 , H04B7/26 , H04J3/00 , H04J3/16 , H04L27/18 , H04L27/22 , H04L27/38 , H04J3/02 , H04B1/40
Abstract: There is provided a method of digital Automatic Gain Control (AGC) in areceiver having limited dynamic range, particularly for discontinuous signals. The method comprises 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 AGC. The method for Automatic Gain Control (AGC) of discontinuous signals in a receiver having limited dynamic range is further characterized by: digitizing 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 sensitivity to establish a desired relationship between the AGC'd signal and the dynamic range limitation.
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公开(公告)号：CA2003580C
公开(公告)日：1993-11-09
申请号：CA2003580
申请日：1989-11-22
Applicant: MOTOROLA INC
Inventor： BORTH DAVID E , KEPLER JAMES F M
IPC: H04L27/14 , H04L27/00 , H04L27/18 , H04L27/227 , H04B1/16
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, detecting the frequency difference between the carrier frequency and the phase of the reference oscillator, and adjusting the frequency of the reference oscillator to eliminate the frequency difference. It is further characterized by digitizing the modulated carrier in quadrature, sampling the modulated carrier in quadrature at a multiple of the modulated bit rate, rotating phases toward arctangent (I/Q)=0 to remove the effects of quadrature data (I/Q) modulated onto the carrier, detecting the frequency difference between the carrier frequency and the frequency of a Voltage Controlled type of reference oscillator with a phase trajectory estimator, adjusting the frequency of the reference oscillator by the frequency difference, and establishing and generating the requisite correction voltage for a Voltage Controlled type of reference oscillator (VCO) with the phase trajectory estimator.
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公开(公告)号：GB2249691B
公开(公告)日：1994-06-08
申请号：GB9200157
申请日：1992-01-06
Applicant: MOTOROLA INC
Inventor： WIJAS THOMAS S , ENDERICH MARK A , KEPLER JAMES F M
Abstract: A double annular ring gasket (202) interfaces a speaker (201) to a housing (200) in a portable radiotelephone, providing a conformal and acoustic seal between the speaker (201) and the housing (200), and compensating for dimensional tolerance between the housing (200) and the circuit board subassembly (204) on which the speaker (201) is mounted. The gasket (201) includes outer ring (205), inner ring (206) and intermediate ring (207) therebetween. The gasket (202) is inserted into a cavity (203) in the housing (200). Then, the speaker (201), as part of a printed circuit board subassembly (204), is pressed into place against the outer ring (205) of gasket (202) to form an axial seal and the inner ring (206) is deformed radially by the speaker (201) to form a conformal seal.
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公开(公告)号：AU7689591A
公开(公告)日：1991-11-27
申请号：AU7689591
申请日：1991-04-09
Applicant: MOTOROLA INC
Inventor： ARENS JOHN W , DORTH DAVID E , KEPLER JAMES F M
Abstract: There is provided a mechanism for Automatic Gain Control in a receiver. It comprises: determining, within a certain dynamic range, the difference in power between the desired signal and a signal received, and providing open loop gain control for the signal in response to the differential so determined, scaled by the receiver's gain characteristics, such that the signal is positioned within dynamic range so as to reduce saturation and noise.
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公开(公告)号：CA2003688C
公开(公告)日：1993-10-05
申请号：CA2003688
申请日：1989-11-23
Applicant: MOTOROLA INC
Inventor： BORTH DAVID E , KEPLER JAMES F M
Abstract: There is provided a method of and apparatus for Automatic Frequency Control (AFC) of pure sine waves (PSW). It comprises discriminating to detect frequency differences between a received pure sine wave and a reference frequency, integrating the frequency differences to average the differences, and adjusting the reference frequency to eliminate the frequency difference. It is further characterized by digitizing, in quadrature, the received pure sine wave, mixing the received pure sine wave with a complex sinusoid to translate the pure sine wave to baseband, quadrature filtering the mixed sine wave, cross-product discriminating to detect frequency differences between a received pure sine wave and a reference frequency, integrating the frequency differences to average the differences, selectively calculating the mean/variance between the pure sine wave and the reference frequency, and adjusting the reference frequency of a Voltage Controlled Oscillator to eliminate the frequency difference.
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Patent Agency Ranking
公开(公告)号：CA2003580A1
公开(公告)日：1990-06-16
申请号：CA2003580
申请日：1989-11-22
Applicant: MOTOROLA INC
Inventor： BORTH DAVID E , KEPLER JAMES F M
IPC: H04L27/14 , H04L27/00 , 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 ( 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).
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公开(公告)号：GB2249691A
公开(公告)日：1992-05-13
申请号：GB9200157
申请日：1992-01-06
Applicant: MOTOROLA INC
Inventor： WIJAS THOMAS S , ENDERICH MARK A , KEPLER JAMES F M
IPC: H04M1/03
Abstract: A double annular ring gasket (202) interfaces a speaker (201) to a housing (200) in a portable radiotelephone, providing a conformal and acoustic seal between the speaker (201) and the housing (200), and compensating for dimensional tolerances between the housing (200) and the circuit board subassembly (204) on which the speaker (201) is mounted. The gasket (201) includes outer ring (205), inner ring (206) and intermediate ring (207) therebetween. The gasket (202) is inserted into a cavity (203) in the housing (200). Then, the speaker (201), as part of a printed circuit board subassembly (204), is pressed into place against the outer ring (205) of gasket (202) to form an axial seal and the inner ring (206) is deformed radially by the speaker (201) to form a conformal seal.
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公开(公告)号：CA2062776A1
公开(公告)日：1991-10-28
申请号：CA2062776
申请日：1991-04-09
Applicant: MOTOROLA INC
Inventor： ARENS JOHN W , BORTH DAVID E , KEPLER JAMES F M
Abstract: There is provided a mechanism for Automatic Gain Control in a receiver. It comprises: determining, within a certain dynamic range, the difference in power between the desired signal and a signal received, and providing open loop gain control for the signal in response to the differential so determined, scaled by the receiver's gain characteristics, such that the signal is positioned within dynamic range so as to reduce saturation and noise.
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公开(公告)号：DD292789A5
公开(公告)日：1991-08-08
申请号：DD33574189
申请日：1989-12-15
Applicant: MOTOROLA INC
Inventor： BORTH DAVID E , KEPLER JAMES F M
Abstract: There is provided a method of and apparatus for Automatice Frequency Control (AFC) of pure sine waves (PSW). It is characterized by discriminating to detect frequency differences between a received pure sine wave and a reference frequency (20), integrating (30) the frequency differences to average the differences, and adjusting (40) the reference frequency (80) to eliminate the frequency difference. It is further characterized by digitizing, in quadrature, the received pure sine wave (70), mixing (50) the received pure sine wave with a complex sinusoid to translate the pure sine wave to baseband, quadrature filtering (60) the mixed sine wave, cross-product discrimination (20) to detect frequency differences between a received pure sine wave and a reference frequency, integration (30) the frequency differences to average the differences, selectively (100/110) calculating the mean/variance (90) between the pure sine wave and the reference frequency, and adjusting (40) the reference frequency of a Voltage Controlled Oscillator 80 to eliminate the frequency difference.
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公开(公告)号：DD292788A5
公开(公告)日：1991-08-08
申请号：DD33574089
申请日：1989-12-15
Applicant: MOTOROLA INC
Inventor： BORTH DAVID E , KEPLER JAMES F M
IPC: H04L27/14 , H04L27/00 , H04L27/18 , H04L27/227 , H03J7/02
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).
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