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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
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：BR9606630A
公开(公告)日：1998-01-06
申请号：BR9606630
申请日：1996-09-11
Applicant: QUALCOMM INC
Inventor： PITTA THOMAS A , PETERZELL PAUL E , KORNFELD RICHARD K , WEILAND ANA L , WALLACE RAYMOND C
Abstract: A dual-band antenna system for use in a portable communications device is disclosed herein. The antenna system includes an antenna element for radiating electromagnetic energy within low-band and high-band wavelength ranges. In a preferred embodiment, a low-band isolator network, coupled to the antenna element, provides signal isolation between high-band and low-band signal paths during high-band operation. Similarly, a high-band isolator network provides signal isolation, during operation over the low-band range of wavelengths, between the high-band and low-band signal paths. During transmit and receive operation, low-band and high-band electromagnetic energy directed through the antenna is passed by the low-band and high-band isolator networks, respectively. Also included are low-band and high-band matching networks which couple the low-band and high-band isolator networks to low-band and high-band transceiver circuitry.
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公开(公告)号：FI964345A0
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：CA2434048C
公开(公告)日：2011-01-04
申请号：CA2434048
申请日：2002-01-10
Applicant: QUALCOMM INC
Inventor： PETERZELL PAUL E , MALDONADO DAVID , GARD KEVIN , SEE PUAY HOE ANDREW , DUNWORTH JEREMY D , SAHOTA GURKANWAL KAMAL
Abstract: A system and method for generating a local oscillator (LO) frequency in a zero intermediate frequency (IF) receiver or transmitter is presented. A signal is received from a voltage controlled oscillator (VCO). The signal has a VCO frequency. The VCO frequency is divided by a number N to produce a signal having a divided-down frequency. The signal having the VCO frequency is then mixed with the signal having the divided-down frequency to produce an output signal having an output frequency. Local oscillator leakage is reduced. Thus, the receiver or transmitter may operate in multiple wireless communication bands and modes and meet the associated specifications.
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公开(公告)号：AU2007224396B2
公开(公告)日：2010-07-08
申请号：AU2007224396
申请日：2007-10-15
Applicant: QUALCOMM INC
Inventor： KANG INJUP , HOLENSTEIN CHRISTIAN , CHALLA RAGHU , WALKER BRETT C , SIH GILBERT C , LI TAO , SEVERSON MATTHEW L , RAGHUPATHY ARUN , PETERZELL PAUL E
Abstract: An apparatus and method in a wireless communication system, the apparatus comprising: first means for amplifying a received signal; means for cancelling a DC offset in the amplified signal; second means for digitally amplifying the DC offset cancelled signal; and means for measuring the digitally amplified signal and to control the gains of the first and second amplifying means.
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Patent Agency Ranking
公开(公告)号：AU2007224394B2
公开(公告)日：2010-07-08
申请号：AU2007224394
申请日：2007-10-15
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C , KANG INJUP , WALKER BRETT C , LI TAO , PETERZELL PAUL E , SEVERSON MATTHEW L , RAGHUPATHY ARUN , HOLENSTEIN CHRISTIAN , CHALLA RAGHU
Abstract: An apparatus and method in a wireless communication system, the apparatus comprising: first means for amplifying a received signal; means for cancelling a DC offset in the amplified signal; second means for digitally amplifying the DC offset cancelled signal; and means for measuring the digitally amplified signal and to control the gains of the first and second amplifying means.
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公开(公告)号：AU2007224394A1
公开(公告)日：2007-11-01
申请号：AU2007224394
申请日：2007-10-15
Applicant: QUALCOMM INC
Inventor： SIH GILBERT C , KANG INJUP , WALKER BRETT C , LI TAO , PETERZELL PAUL E , SEVERSON MATTHEW L , RAGHUPATHY ARUN , HOLENSTEIN CHRISTIAN , CHALLA RAGHU
Abstract: An apparatus and method in a wireless communication system, the apparatus comprising: first means for amplifying a received signal; means for cancelling a DC offset in the amplified signal; second means for digitally amplifying the DC offset cancelled signal; and means for measuring the digitally amplified signal and to control the gains of the first and second amplifying means.
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公开(公告)号：FI20060862A
公开(公告)日：2006-09-27
申请号：FI20060862
申请日：2006-09-27
Applicant: QUALCOMM INC
Inventor： WHEATLEY III CHARLES E , KORNFELD RICHARD K , PETERZELL PAUL E , WEILAND ANA L
IPC: H04B1/06 , H03G1/00 , H03G3/30 , H04B20060101 , H04B1/10 , H04B1/16 , H04B1/18 , H04B1/40 , H04B1/7075 , H04B1/7097 , H04B3/06 , H04B7/005 , H04B7/26 , H04B15/00
Abstract: An apparatus to increase a radio receiver's immunity to radio frequency interference, the radio receiver receiving a signal, the apparatus comprising: a switch (1105) coupled to the received signal, the switch (1105) having an open position and a closed position; a resistance (1101), a first end of the resistance (1101) being coupled to the closed position of the switch (1105) and a second end of the resistance (1101) being coupled to a ground potential; an amplifier (1101) having an input coupled to the open position of the switch (1105), for generating an amplified received signal at an output; a controller coupled to the switch (1105), for switching the switch (1105) to the closed position in response to the received signal exceeding a predetermined power level, said received signal conducting through said switch (1105) and said resistance (1101) to ground potential when said switch (1105) is in said closed position; and said resistance (1101) creating an impedance mismatch at the input to said amplifier (1110) when said switch (1105) is in closed position, thereby reducing the gain contributed by said amplifier (1110).
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公开(公告)号：CA2553453A1
公开(公告)日：2005-08-11
申请号：CA2553453
申请日：2005-01-14
Applicant: QUALCOMM INC
Inventor： SAHOTA GURKANWAL KAMAL , REEVES ROBERT , SEE PUAY HOE , PETERZELL PAUL E , RAGHUPATHY ARUN
Abstract: Methods and apparatus for amplifier AM and PM predistortion and autocalibration. AM and PM amplifier distortion can be corrected using predistortion. The AM and PM distortion characteristics of the amplifier are determined using an autocalibration technique. The amplifier characteristics can be stored in distinct look up tables (526, 712). Alternatively, the inverse of the amplifier characteristics can be stored in distinct look up tables. Signals that are to be amplified are characterized in polar format having a phase component with a normalized magnitude and a magnitude component. The phase component can be predistorted by applying the inverse o f the PM distortion characteristics to the signal. Similarly, the magnitude component can be predistorted by applying the inverse of the AM distortion characteristics to the signal. The predistorted phase component can be amplified using the previously characterized amplifier. The predistorted magnitude component can be used to set the gain of the previously characterized amplifier.
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公开(公告)号：AU4339602A
公开(公告)日：2002-06-24
申请号：AU4339602
申请日：2001-10-24
Applicant: QUALCOMM INC
Inventor： SEE PUAY HOE , PETERZELL PAUL E , WALKER BRETT C
Abstract: A zero Intermediate Frequency (IF) transmitter and receiver are implemented within a transceiver to eliminate interference in the receive band. An output of a tunable high oscillator to generate a frequency source that is an integer multiple of the desired transmit LO frequency. The frequency source is coupled to an amplitude limiter and frequency divider. The output of the frequency divider is used as the transmit LO to directly upconvert baseband signals to the desired output frequency without the need for an IF stage. Direct upconversion of the baseband transmit signals without an IF stage eliminates spurious frequency products that are produced in the receive band.
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