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公开(公告)号：DE69027860D1
公开(公告)日：1996-08-22
申请号：DE69027860
申请日：1990-11-26
Applicant: MOTOROLA INC
Inventor： BIRCHLER MARK , JASPER STEVEN
Abstract: A method for reducing noise caused by fading in FM radio systems . The algorithm described operates on a sequence of complex samples received at the input of the discriminator (501) from the output of the IF filter of a digitally implemented radio. After determination of magnitude (502), which yields the raw envelope of the received signal, the raw envelope information is processed via parallel paths to determine characteristics indicative of shape, amplitude and time of occurrence of noise pulses. The output signal from the discriminator (501) is processed (508) to determine noise pulse direction. A pulse generator (510) produces counter pulses based upon the previously determined characteristcs, and the counter pulses are combined (513) with the discriminator output to substantially cancel the noise pulses.
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公开(公告)号：DE69131503T2
公开(公告)日：2000-03-23
申请号：DE69131503
申请日：1991-12-16
Applicant: MOTOROLA INC
Inventor： WILSON ALAN , CUDAK MARK , HIBEN BRADLEY , ZIOLKO ERIC , JASPER STEVEN
Abstract: A transceiver compatible with both wide channel constant envelope 4 level FSK FM modulation and narrow channel pi /4 differential QPSK linear modulation allows compatible interaction between modified constant envelope and non-constant envelope transmitters. All Nyquist filtering occurs in the transmitters, and none in the receiver.
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公开(公告)号：DE69227506T2
公开(公告)日：1999-06-02
申请号：DE69227506
申请日：1992-08-10
Applicant: MOTOROLA INC
Inventor： JASPER STEVEN , BIRCHLER MARK
Abstract: The ratio of peak power level to average power level in a power amplifier used in a QAM communication system transmitter can be reduced by preselecting magnitudes and phase angles of complex-valued pilot symbols used in multi-channel, N-level QAM.
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公开(公告)号：DE69113962D1
公开(公告)日：1995-11-23
申请号：DE69113962
申请日：1991-05-30
Applicant: MOTOROLA INC
Inventor： JASPER STEVEN , BIRCHLER MARK
Abstract: A method for implementing diversity reception to counteract effects of channel fading on a transmitted information signal. In diversity receive paths, estimates of complex channel gain are computed based upon pilot symbols inserted from time to time in the transmitted information symbol stream. Phase corrected and weighted samples from the diversity paths are summed prior to the decision process. The squared magnitudes of the diversity path channel gains are summed to provide the proper threshold adjustment.
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公开(公告)号：DE69227506D1
公开(公告)日：1998-12-10
申请号：DE69227506
申请日：1992-08-10
Applicant: MOTOROLA INC
Inventor： JASPER STEVEN , BIRCHLER MARK
Abstract: The ratio of peak power level to average power level in a power amplifier used in a QAM communication system transmitter can be reduced by preselecting magnitudes and phase angles of complex-valued pilot symbols used in multi-channel, N-level QAM.
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Patent Agency Ranking
公开(公告)号：DE69113962T2
公开(公告)日：1996-05-15
申请号：DE69113962
申请日：1991-05-30
Applicant: MOTOROLA INC
Inventor： JASPER STEVEN , BIRCHLER MARK
Abstract: A method for implementing diversity reception to counteract effects of channel fading on a transmitted information signal. In diversity receive paths, estimates of complex channel gain are computed based upon pilot symbols inserted from time to time in the transmitted information symbol stream. Phase corrected and weighted samples from the diversity paths are summed prior to the decision process. The squared magnitudes of the diversity path channel gains are summed to provide the proper threshold adjustment.
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公开(公告)号：HU9500236D0
公开(公告)日：1995-03-28
申请号：HU9500236
申请日：1994-05-20
Applicant: MOTOROLA INC
Inventor： BIRCHLER MARK , JASPER STEVEN , WILSON TIMOTHY
Abstract: A receiver may reduce the effects of distortion when determining signal usability in the following manner. Upon receiving a signal, the receiver separates a desired component, an undesired component, and a distortion component, wherein the desired component includes the signal that was originally transmitted and the undesired component includes interference and noise. Having isolated the distortion component, it can be mitigated such that the usability of the signal received can be determined based on a ratio between the desired and undesired components.
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公开(公告)号：DE69419918T2
公开(公告)日：2000-03-16
申请号：DE69419918
申请日：1994-05-11
Applicant: MOTOROLA INC
Inventor： BIRCHLER MARK , JASPER STEVEN , WILSON TIMOTHY
Abstract: A receiver that receives a stream of information symbols may detect the usability of the stream of information symbols received as follows. Upon receiving the stream of information symbols, the receiver separates the stream of information symbols into a desired portion and an undesired portion wherein the desired portion is the originally transmitted stream of information symbols and the undesired portion is interference and noise. From the undesired portion and the desired portion, the usability can be determined based on a ratio of the two portions.
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公开(公告)号：DE69228801T2
公开(公告)日：1999-10-07
申请号：DE69228801
申请日：1992-09-23
Applicant: MOTOROLA INC
Inventor： JASPER STEVEN , BIRCHLER MARK
Abstract: In a digital communication system in which pulse-shape filtered sync, pilot, and data symbols, arranged in successive time slots, modulate sub-channel carriers via sub-channel mixers to form sub-channel symbol streams for combination into a composite signal for transmission, deterministic portions of each time slot are rendered identical by determining phase difference of sub-channel carriers and rotating the phase of each sub-channel symbol stream by an amount equal to the phase difference, but with opposite sign.
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公开(公告)号：DE69419918D1
公开(公告)日：1999-09-09
申请号：DE69419918
申请日：1994-05-11
Applicant: MOTOROLA INC
Inventor： BIRCHLER MARK , JASPER STEVEN , WILSON TIMOTHY
Abstract: A receiver that receives a stream of information symbols may detect the usability of the stream of information symbols received as follows. Upon receiving the stream of information symbols, the receiver separates the stream of information symbols into a desired portion and an undesired portion wherein the desired portion is the originally transmitted stream of information symbols and the undesired portion is interference and noise. From the undesired portion and the desired portion, the usability can be determined based on a ratio of the two portions.
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