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公开(公告)号：CA2233692C
公开(公告)日：2007-07-24
申请号：CA2233692
申请日：1996-09-16
Applicant: QUALCOMM INC
Inventor： WILSON NATHANIEL B
Abstract: The present invention provides linear, digital automatic gain control (AGC) in a radio. A received signal is demodulated to provide I and Q digital baseband signals. A received signal strength indication is determined from these signals and the resulting digital signal is adjusted to provide a logarithmic response (205). This signal is then integrated (210) to provide a digital receive AGC adjust signal. For the transmit AGC adjust, the digital receive AGC adjust signal is filtered (215) and then summed (270) with a scaled (260) closed loop power control command (265). The closed loop power control commands (265) are ignored (220) if they would result in increasing the transmit gain beyond the amplifier's designed maximum output. The outputs of the transmit and receive AGC amplifiers are linearized by transmit and receive linearizers, (225) and (240) respectively, which pre-distort the digital AGC adjust signals prior to digital to analog conversion (230) and (245).
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公开(公告)号：AT229709T
公开(公告)日：2002-12-15
申请号：AT96933039
申请日：1996-09-16
Applicant: QUALCOMM INC
Inventor： WILSON NATHANIEL B
Abstract: The present invention provides linear, digital automatic gain control (AGC) in a radio. A received signal is demodulated to provide I and Q digital baseband signals. A received signal strength indication is determined from these signals and the resulting digital signal is adjusted to provide a logarithmic response. This signal is then integrated to provide a digital receive AGC adjust signal. For the transmit AGC adjust, the digital receive AGC adjust signal is filtered and then summed with a scaled closed loop power control command. The closed loop power control commands are ignored if they would result in increasing the transmit gain beyond the amplifier's designed maximum output. The result of the sum operation converted from digital to analog for adjusting the amplifier. The outputs of the transmit and receive AGC amplifiers are linearized by transmit and receive linearizers, respectively, which pre-distort the digital AGC adjust signals prior to digital to analog conversion.
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公开(公告)号：ES2158088T3
公开(公告)日：2001-09-01
申请号：ES95911058
申请日：1995-02-17
Applicant: QUALCOMM INC
Inventor： WEILAND ANA L , KORNFELD RICHARD K , KERR RICHARD J , MALONEY JOHN E , WILSON NATHANIEL B
Abstract: The process and apparatus of the present invention limits the output power of a radiotelephone, operating in a cellular system in the preferred embodiment. This ensures the transmitted sidebands and synthesizer phase noise remains within a certain specification. This is accomplished by power detection and a correction accumulator that together generate a gain control signal by limiting the gain adjustment to a maximum value, even when the cell site communicating with the radiotelephone is sending power turn-up commands to the radiotelephone. This process includes dynamically correcting the output level of the transmitter due to gain variations in the transmitter stages or gain control elements.
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公开(公告)号：AT200946T
公开(公告)日：2001-05-15
申请号：AT95911058
申请日：1995-02-17
Applicant: QUALCOMM INC
Inventor： WEILAND ANA L , KORNFELD RICHARD K , KERR RICHARD J , MALONEY JOHN E , WILSON NATHANIEL B
Abstract: The process and apparatus of the present invention limits the output power of a radiotelephone, operating in a cellular system in the preferred embodiment. This ensures the transmitted sidebands and synthesizer phase noise remains within a certain specification. This is accomplished by power detection and a correction accumulator that together generate a gain control signal by limiting the gain adjustment to a maximum value, even when the cell site communicating with the radiotelephone is sending power turn-up commands to the radiotelephone. This process includes dynamically correcting the output level of the transmitter due to gain variations in the transmitter stages or gain control elements.
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公开(公告)号：DK0706730T3
公开(公告)日：1999-02-08
申请号：DK95917193
申请日：1995-04-28
Applicant: QUALCOMM INC
Inventor： WILSON NATHANIEL B , BLACK PETER J , PETERZELL PAUL E
Abstract: An automatic gain control (AGC) and D.C. offset correction method and apparatus for controlling signal power of a received RF signal within a dual mode quadrature receiver is disclosed herein. In a preferred implementation the automatic gain control apparatus may be adjusted to provide a desired control response to various fading characteristics of a received FM, FSK, GMSK, QPSK, or BPSK signal. The AGC apparatus includes an adjustable gain amplifier having an input port for receiving an input signal, a control port for receiving a gain control signal, and an output port for providing an output signal. A quadrature downconverter coupled to the output port serves to translate the frequency of the output signal to a baseband frequency, thereby producing baseband signals. In a preferred implementation the downconverter is operative to map the carrier frequency of the output signal to a baseband frequency offset by a predetermined margin from D.C. Two high gain active lowpass filters provide out-of-band signal rejection for the baseband signals. A D.C. feedthrough suppression loop, disposed to receive said baseband signal, suppresses D.C. offsets produced by the downconverter and lowpass filters, hence providing a compensated baseband signal. The AGC apparatus is further disposed to generate a received power signal based on the power of the output signal. A saturating integrator compares the received power signal to a reference signal and produces the gain control signal by integrating or by refraining from integration based on values of the reference, received power signal, and gain control signals, thereby extending the usable dynamic range of the receiver for FM mode.
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Patent Agency Ranking
公开(公告)号：ZA9510509B
公开(公告)日：1996-05-30
申请号：ZA9510509
申请日：1995-12-11
Applicant: QUALCOMM INC
Inventor： BLACK PETER J , WILSON NATHANIEL B
IPC: H04L27/10 , H04B1/04 , H04B1/40 , H04B7/26 , H04L25/49 , H04L27/14 , H04L27/233 , H04W4/18 , H04W88/06 , H03D , H04B , H04J , H04L
Abstract: A dual-mode digital communication system for communicating an information signal during operation in frequency-modulated (FM) and multiple-access modes is disclosed herein. The digital communication system includes a dual-mode transmitter for transmitting the information signal using an FM communication signal during FM mode operation, and for transmitting the information signal using a multiple-access communication signal during multiple-access mode operation. The communication system further includes a dual-mode receiver for receiving the FM communication signal during FM mode operation, and for receiving the multiple-access communication signal during multiple-access mode operation. Incorporated within the dual-mode receiver is a digital demodulator for recovering the information signal from the received FM signal during operation in the FM mode, and for recovering the information signal from the received multiple-access signal during multiple-access mode operation. In a preferred implementation the dual-mode transmitter is disposed to convert a first sequence of binary data within the information signal into a sampled modulation waveform, and to provide the FM communication signal by modulating a carrier signal based at least in part on the sampled modulation waveform. The dual-mode transmitter may also be configured to multiplex a second sequence of wideband message data with the sampled modulation waveform so as to form a composite FM modulation waveform.
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公开(公告)号：BR9505674A
公开(公告)日：1996-01-16
申请号：BR9505674
申请日：1995-02-17
Applicant: QUALCOMM INC
Inventor： WEILAND ANA L , KORNFELD RICHARD K , KERR RICHARD J , MALONEY JOHN E , WILSON NATHANIEL B
Abstract: The process and apparatus of the present invention limits the output power of a radiotelephone, operating in a cellular system in the preferred embodiment. This ensures the transmitted sidebands and synthesizer phase noise remains within a certain specification. This is accomplished by power detection and a correction accumulator that together generate a gain control signal by limiting the gain adjustment to a maximum value, even when the cell site communicating with the radiotelephone is sending power turn-up commands to the radiotelephone. This process includes dynamically correcting the output level of the transmitter due to gain variations in the transmitter stages or gain control elements.
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公开(公告)号：CA2188446A1
公开(公告)日：1995-11-09
申请号：CA2188446
申请日：1995-04-28
Applicant: QUALCOMM INC
Inventor： PETERZELL PAUL E , WILSON NATHANIEL B , BLACK PETER J
Abstract: An automatic gain control (AGC) apparatus for a digital receiver is disclosed herein. The AGC apparatus includes an adjustable gain amplifier (18) having an input port for receiving an input signal, a control port for receiving a gain control signal, and an output port for providing an output signal. The AGC apparatus further includes a measurement circuit for generating a received power signal based on the power of the output signal. A saturating integrator (22) compares the received power signal to a reference signal and generates a gain control signal in response to a result of the comparison. The saturating integrator (22) includes a decision circuit (46) for enabling integration based on values of the received power signal, the reference signal, and the gain control signal. In a preferred implementation, the utilization of an input limiter in conjunction with an analog to digital converter enables accommodation of an increased input signal dynamic range.
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公开(公告)号：CA2158577A1
公开(公告)日：1995-08-31
申请号：CA2158577
申请日：1995-02-17
Applicant: QUALCOMM INC
Inventor： WEILAND ANA L , KORNFELD RICHARD K , KERR RICHARD J , MALONEY JOHN E , WILSON NATHANIEL B
Abstract: The process and apparatus of the present invention limits the output power of a radiotelephone, operating in a cellular system in the preferred embodiment. This ensures the transmitted sidebands and synthesizer phase noise remains within a certain specification. This is accomplished by power detection and a correction accumulator that together generate a gain control signal by limiting the gain adjustment to a maximum value, even when the cell site communicating with the radiotelephone is sending power turn-up commands to the radiotelephone. This process includes dynamically correcting the output level of the transmitter due to gain variations in the transmitter stages or gain control elements.
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公开(公告)号：CA2188446C
公开(公告)日：2004-07-06
申请号：CA2188446
申请日：1995-04-28
Applicant: QUALCOMM INC
Inventor： PETERZELL PAUL E , WILSON NATHANIEL B , BLACK PETER J
Abstract: An automatic gain control (AGC) apparatus for a digital receiver is disclose d herein. The AGC apparatus includes an adjustable gain amplifier (18) having an input port for receiving an input signal, a co ntrol port for receiving a gain control signal, and an o utput port for providing an output signal. The AGC apparatus further includes a measur ement circuit for generating a received power signal bas ed on the power of the output signal. A saturating integrator (22) compares th e received power signal to a reference signal and genera tes a gain control signal in response to a result of the comparison. The saturati ng integrator (22) includes a decision circuit (46) for enabling integration based on values of the received power signal, the reference sign al, and the gain control signal. In a preferred impleme ntation, the utilization of an input limiter in conjunction with an analog to digital converter enables accommodation of an increased input s ignal dynamic range.
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