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    11.
    发明专利
    未知

    公开(公告)号：AT264025T

    公开(公告)日：2004-04-15

    申请号：AT95944116

    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 ,  H04J15/00

    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.

    12.
    发明专利
    未知

    公开(公告)号：ES2188790T3

    公开(公告)日：2003-07-01

    申请号：ES96933039

    申请日：1996-09-16

    Applicant: QUALCOMM INC

    Inventor： WILSON NATHANIEL B

    IPC: H03G3/20 ,  H03F1/32 ,  H03G3/30

    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.

    METHOD AND APPARATUS FOR AUTOMATIC GAIN CONTROL AND DC OFFSET CANCELLATION IN QUADRATURE RECEIVER
    13.
    发明专利
    METHOD AND APPARATUS FOR AUTOMATIC GAIN CONTROL AND DC OFFSET CANCELLATION IN QUADRATURE RECEIVER 未知

    公开(公告)号：CA2163883C

    公开(公告)日：2003-01-28

    申请号：CA2163883

    申请日：1995-04-28

    Applicant: QUALCOMM INC

    Inventor： WILSON NATHANIEL B ,  BLACK PETER J ,  PETERZELL PAUL E

    IPC: H03G3/20 ,  H03D3/00 ,  H03D3/24 ,  H03D7/16 ,  H03G3/30 ,  H04B1/30 ,  H04L27/14 ,  H04L27/22

    Abstract: An automatic gain control (AGC) and D.C. offset correction method and appara tus for controlling signal power of a received RF signal within a dual mode quadrature receiver is disclosed herein. The AGC a pparatus includes an adjustable gain amplifier (18). A quadrature downconverter (20) coupled to the amplifier (18) serves to transl ate the frequency of the output signal to a baseband fre quency which is offset by a predetermined margin from D.C. Two high gain active low pass filters (76 and 78) provide out-of-band signal reje ction for the baseband signals. A D.C. feedthrough suppression loop supresses D.C. offsets produced by a downconverter (20) and the lowpas s filters (76 and 78). The AGC apparatus also generates a received power signa l based on the power of the output signal. A saturating integrator compares the received power signal to a reference signal and prod uces the gain control signal by integrating or by refrai ning from integration based on values of the reference, received power signal, an d gain control signals.

    15.
    发明专利
    未知

    公开(公告)号：ES2115380T3

    公开(公告)日：1998-06-16

    申请号：ES95917193

    申请日：1995-04-28

    Applicant: QUALCOMM INC

    Inventor： WILSON NATHANIEL B ,  BLACK PETER J ,  PETERZELL PAUL E

    IPC: H03D3/00 ,  H03D3/24 ,  H03G3/20 ,  H03D7/16 ,  H03G3/30 ,  H04B1/30 ,  H04L27/14 ,  H04L27/22

    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.

    16.
    发明专利
    未知

    公开(公告)号：AT164974T

    公开(公告)日：1998-04-15

    申请号：AT95917193

    申请日：1995-04-28

    Applicant: QUALCOMM INC

    Inventor： WILSON NATHANIEL B ,  BLACK PETER J ,  PETERZELL PAUL E

    IPC: H03G3/20 ,  H03D3/00 ,  H03D3/24 ,  H03D7/16 ,  H03G3/30 ,  H04B1/30 ,  H04L27/14 ,  H04L27/22

    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.

    18.
    发明专利
    未知

    公开(公告)号：FI972590A0

    公开(公告)日：1997-06-17

    申请号：FI972590

    申请日：1997-06-17

    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 ,  H04B ,  H04J

    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.

    LINEARIZED DIGITAL AUTOMATIC GAIN CONTROL
    19.
    发明专利
    LINEARIZED DIGITAL AUTOMATIC GAIN CONTROL 未知

    公开(公告)号：CA2233692A1

    公开(公告)日：1997-03-20

    申请号：CA2233692

    申请日：1996-09-16

    Applicant: QUALCOMM INC

    Inventor： WILSON NATHANIEL B

    IPC: H03G3/20 ,  H03F1/32 ,  H03G3/30 ,  H04B7/005 ,  H04Q7/32

    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).

    Linearized digital automatic gain control
    20.
    发明专利
    Linearized digital automatic gain control 未知

    公开(公告)号：ZA967426B

    公开(公告)日：1997-03-10

    申请号：ZA967426

    申请日：1996-09-02

    Applicant: QUALCOMM INC

    Inventor： WILSON NATHANIEL B

    IPC: H03G3/20 ,  H03F1/32 ,  H03G3/30 ,  H04B ,  H03G ,  G05B

    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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