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公开(公告)号：AU702217B2
公开(公告)日：1999-02-18
申请号：AU2398695
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 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 compares the received power signal to a reference signal and generates an gain control signal in response to a result of the comparison. The saturating integrator includes a decision circuit 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. Accordingly, the AGC apparatus is capable of being used in digital demodulation of FM signals. The AGC apparatus may also be employed within a dual mode receiver designed to process both FM and code division multiple access (CDMA) input signals.
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公开(公告)号：NZ319397A
公开(公告)日：1998-07-28
申请号：NZ31939796
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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43.发明专利
公开(公告)号：AU694514B2
公开(公告)日：1998-07-23
申请号：AU2398995
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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公开(公告)号：FI980592A0
公开(公告)日：1998-03-17
申请号：FI980592
申请日：1998-03-17
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：MX9704695A
公开(公告)日：1997-10-31
申请号：MX9704695
申请日：1995-12-19
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 , H04B01/40 , H04J15/00
Abstract: En la presente se expone un sistema de comunicaciones digitales de doble modo para comunicar una señal de informacion durante la operacion en modos de frecuencia modulada (FM) y de multiple acceso. El sistema de comunicacion digital incluye un transmisor de doble modo 14 para transmitir la señal de informacion utilizando una señal de comunicacion de FM durante la operacion en modo de FM, y para transmitir la señal de informacion que utiliza una señal de comunicacion de multiple acceso durante la operacion en modo de multiple acceso. El sistema de comunicacion incluye además un receptor de doble modo 16 para recibir la señal de comunicacion de FM durante la operacion en modo de FM, y para recibir la señal de comunicacion de multiple acceso durante la operacion en modo de multiple acceso. Se incorpora dentro del receptor de doble modo 16 un demodulador digital 96 para recuperar la señal de informacion a partir de la señal de FM recibida durante la operacion en el modo de FM, y para recuperar la señal de informacion a partir de la señal de multiple acceso recibida durante la operacion en modo de multiple acceso.
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Patent Agency Ranking
公开(公告)号：BR9507564A
公开(公告)日：1997-08-05
申请号：BR9507564
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 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 compares the received power signal to a reference signal and generates an gain control signal in response to a result of the comparison. The saturating integrator includes a decision circuit 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. Accordingly, the AGC apparatus is capable of being used in digital demodulation of FM signals. The AGC apparatus may also be employed within a dual mode receiver designed to process both FM and code division multiple access (CDMA) input signals.
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公开(公告)号：AU674475B2
公开(公告)日：1996-12-19
申请号：AU1879795
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：FI964345A
公开(公告)日：1996-10-28
申请号：FI964345
申请日：1996-10-28
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 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 compares the received power signal to a reference signal and generates an gain control signal in response to a result of the comparison. The saturating integrator includes a decision circuit 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. Accordingly, the AGC apparatus is capable of being used in digital demodulation of FM signals. The AGC apparatus may also be employed within a dual mode receiver designed to process both FM and code division multiple access (CDMA) input signals.
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公开(公告)号：FI956286A
公开(公告)日：1996-02-26
申请号：FI956286
申请日：1995-12-27
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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公开(公告)号：AU2398695A
公开(公告)日：1995-11-29
申请号：AU2398695
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 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 compares the received power signal to a reference signal and generates an gain control signal in response to a result of the comparison. The saturating integrator includes a decision circuit 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. Accordingly, the AGC apparatus is capable of being used in digital demodulation of FM signals. The AGC apparatus may also be employed within a dual mode receiver designed to process both FM and code division multiple access (CDMA) input signals.
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