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公开(公告)号：CZ256393A3
公开(公告)日：1994-03-16
申请号：CZ256393
申请日：1993-01-21
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPHER P , CARNEY MICHAEL J , BAKER JAMES C
Abstract: The method of synchronizing a sampling clock signal to a received data signal, the clock recovery circuit generates several clock signals at the symbol rate, with each clock signal having a unique phase. To permit fast initial acquisition, the set of clock signals includes a pair of clocks which differ in phase by one-half of a symbol interval. Additionally, the clock recovery circuitry generates error signals representing the difference between the phase of the received data signal and the phase of each clock signal. The error signals are processed over multiple symbol times to determine the optimal sampling phase. The clock recovery circuit then adjusts or maintains the phase of the symbol clock to provide the optimal sampling phase.
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公开(公告)号：SE9303908L
公开(公告)日：1994-01-21
申请号：SE9303908
申请日：1993-11-25
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPFER P , CARNEY MICHAEL J
Abstract: A method of and apparatus for compensating a received signal's phase compensates for the distortion caused by the asymmetrical characteristics of a voltage limiter. This compensation allows the received signal to be sampled at the positive and negative zero-crossings reducing the requirements of a local oscillator in a radiotelephone system. First, the phase of the received signal is sampled at the positive and negative zero-crossings, forming a corresponding positive-crossing and a negative-crossing phase value for the received signal. Second, the negative-crossing and positive-crossing phase values are combined, forming a first difference signal. Third, an estimated error signal is formed using the first difference signal. Fourth, the estimated error signal is combined with the positive or negative zero-crossing phase signals, substantially eliminating the asymmetrical distortion.
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公开(公告)号：CA2102194A1
公开(公告)日：1993-09-27
申请号：CA2102194
申请日：1993-01-21
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPHER P , CARNEY MICHAEL J
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公开(公告)号：FI933598A0
公开(公告)日：1993-08-13
申请号：FI933598
申请日：1993-08-13
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPHER P , CARNEY MICHAEL J
IPC: H03D3/00 , H04L7/033 , H04L27/233
Abstract: This patent application discusses a direct phase digitizing apparatus (303) for use in a radiotelephone (101). The direct phase digitizing apparatus (303) accepts a first analog signal (309) having a phase, a voltage range and a first frequency. First, the direct phase digitizer generates an estimated phase map (611) having a second frequency and N-bits of resolution. Second, the direct phase digitizer detects a predetermined-voltage crossing (409) of the first analog signal (309). Third, using the predetermined-voltage crossings, the direct phase digitizer samples the estimated phase map. Fourth, a digital phase signal (623) is generated using the samples of the estimated phase map.
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公开(公告)号：MX9207217A
公开(公告)日：1993-06-01
申请号：MX9207217
申请日：1992-12-11
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPHER P , CARNEY MICHAEL J
IPC: A61F13/15 , H04L27/233 , H03D7/00 , H03D13/00 , G11C11/00
Abstract: The present patent application discusses a frequency translation apparatus for altering the effective frequency of the phase information of an input signal (115). The input signal (115) has a first phase ((theta)(t)) and a first frequency (fi). The phase of the input signal is extracted and digitized at a second frequency (fo), forming a second N-bit digital phase signal ((theta)'(t))(311). The frequency translation apparatus generates a third digital phase signal (319) which approximates the difference between (theta)(t) and (theta)'(t). Then, the frequency translation apparatus combines the second digital phase signal and the third digital phase signal, forming a fourth digital phase signal (307) substantially approximating the first phase signal.
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Patent Agency Ranking
公开(公告)号：FR2768576B1
公开(公告)日：2004-10-29
申请号：FR9810128
申请日：1998-08-06
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPHER P , CARNEY MICHAEL J , BECKER CHRISTOHER J , EBERHARDT MICHAEL A , FRANK COLIN D , RASKY PHILLIP D
IPC: H04B1/7113 , H04B1/7115 , H04B1/7117 , H04B1/69 , H04B7/216
Abstract: A RAKE receiver (112) includes a plurality of fingers (122, 124, 126, 128). Each finger includes a demodulator (402) for demodulating a ray of a multipath signal and a time tracking circuit (404) for controlling the time position of the finger in accordance with time position of the ray. A low delay-spread condition is detected and the positions of two adjacent fingers are controlled to prevent convergence of two or more fingers about a common time position. By maintaining finger timing separation, path diversity is exploited by the RAKE receiver even during the low delay-spread condition to improve receiver performance.
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公开(公告)号：AU735531B2
公开(公告)日：2001-07-12
申请号：AU7861798
申请日：1998-07-31
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPHER P , CARNEY MICHAEL J , BECKER CHRISTOPHER J , EBERHARDT MICHAEL A , FRANK COLIN D , RASKY PHILLIP D
IPC: H04B1/7113 , H04B1/7115 , H04B1/7117 , H04J13/04 , H04B7/216
Abstract: A RAKE receiver (112) includes a plurality of fingers (122, 124, 126, 128). Each finger includes a demodulator (402) for demodulating a ray of a multipath signal and a time tracking circuit (404) for controlling the time position of the finger in accordance with time position of the ray. A low delay-spread condition is detected and the positions of two adjacent fingers are controlled to prevent convergence of two or more fingers about a common time position. By maintaining finger timing separation, path diversity is exploited by the RAKE receiver even during the low delay-spread condition to improve receiver performance.
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公开(公告)号：GB2314742B
公开(公告)日：2001-02-14
申请号：GB9710089
申请日：1997-05-20
Applicant: MOTOROLA INC
Inventor： GOODE STEVEN H , BAKER JAMES C , CARNEY MICHAEL J
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公开(公告)号：BR9803430A
公开(公告)日：1999-11-03
申请号：BR9803430
申请日：1998-09-11
Applicant: MOTOROLA INC
Inventor： ROSA CRISTOPHER P LA , CARNEY MICHAEL J , BECKER CHRISTOPHER J , EBERHARDT MICHAEL A , FRANK COLIN D , RASKY PHILLIP D
IPC: H04B1/7113 , H04B1/7115 , H04B1/7117 , H04Q7/22
Abstract: A RAKE receiver (112) includes a plurality of fingers (122, 124, 126, 128). Each finger includes a demodulator (402) for demodulating a ray of a multipath signal and a time tracking circuit (404) for controlling the time position of the finger in accordance with time position of the ray. A low delay-spread condition is detected and the positions of two adjacent fingers are controlled to prevent convergence of two or more fingers about a common time position. By maintaining finger timing separation, path diversity is exploited by the RAKE receiver even during the low delay-spread condition to improve receiver performance.
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公开(公告)号：FR2703861B1
公开(公告)日：1999-10-29
申请号：FR9404003
申请日：1994-04-06
Applicant: MOTOROLA INC
Inventor： LAROSA CHRISTOPHER P , CARNEY MICHAEL J
IPC: G01R29/02 , H03L7/085 , H04B14/02 , H04L27/233 , H04B1/26
Abstract: A radio receiver directly digitizes the phase of an intermediate frequency (IF) signal with a desired resolution. The frequency of the reference oscillator in the direct phase digitizer is reduced when compared to the frequency previously required for the same resolution. The reduction in the reference oscillator frequency is accomplished by differentiating between IF zero-crossings that occur during the first half of a reference oscillator cycle and zero-crossings which occur during the second half of the reference oscillator cycle. The apparatus utilizes 2 zero-crossing detectors, the first zero-crossing detector is driven by a positive edge of the reference oscillator signal and the second zero-crossing detector is driven by a negative edge of the reference oscillator signal. Depending upon the alignment of the negative edge zero-crossing indicator and the positive edge zero-crossing indicator, the N-bit phase signal is modified or shifted by one-half a phase sector.
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