Predistortion technique for high power amplifiers

    公开(公告)号:AU4718199A

    公开(公告)日:2000-01-17

    申请号:AU4718199

    申请日:1999-06-24

    Applicant: QUALCOMM INC

    Abstract: A predistortion technique for high power amplifiers includes an adaptive predistortion algorithm that operates independently of data samples to write a set of complex gain values, or predistortion parameters, to a lookup table. The algorithm may be processor-driven. The gain values are taken from the lookup table and multiplied by a complex digital baseband waveform. The gain values may first be subjected to interpolation. The downconverted output of the amplifier is measured to gauge the efficacy of the predistortion. Based on the effect of the predistortion upon the ratio of in-band power to out-of-band power, decisions are made on the set of predistortion parameters for the next iteration of the algorithm. The algorithm runs continuously, perturbing parameters and adapting the predistortion functions accordingly in an effort to continually reflect instantaneous amplitude-modulation and phase-modulation relationships that may change over time with temperature variation or component aging.

    12.
    发明专利
    未知

    公开(公告)号:NO972306L

    公开(公告)日:1997-05-21

    申请号:NO972306

    申请日:1997-05-21

    Applicant: QUALCOMM INC

    Abstract: An improved method and system for performing a pilot signal searching operation in anticipation of handoff in mobile station communication between base stations is disclosed herein. The searching operation is described herein as being implemented within a cellular communication system which uses code division multiple access (CDMA) modulation techniques. The mobile station maintains a list of an Active Set of pilot signals transmitted from base stations with which the mobile station is to communicate through, and a Neighbor Set of pilots from base stations within a predetermined proximity of the mobile station. In addition to the Neighbor and Active Sets of pilots, the mobile station maintains a list of Candidate and Pre-Candidate Sets of pilots. Based on analysis of the signal strength of the pilot signals received at the mobile station, base station entries from the Neighbor Set may be assigned to the Pre-Candidate and Candidate Sets, and eventually to the Active set. The searching operation contemplates comparing pilot signal strength measurements corresponding to each base station entry within the Neighbor Set to a first predetermined level. One or more entries from the Neighbor Set having a base station signal strength measurement greater than the first predetermined level may be placed in the Pre-Candidate Set. The strength of the pilot signals associated with entries in the Pre-Candidate Set are then further evaluated to determine eligibility within the Candidate Set, from which are selected the entries comprising the Active Set.

    13.
    发明专利
    未知

    公开(公告)号:NO972306D0

    公开(公告)日:1997-05-21

    申请号:NO972306

    申请日:1997-05-21

    Applicant: QUALCOMM INC

    Abstract: An improved method and system for performing a pilot signal searching operation in anticipation of handoff in mobile station communication between base stations is disclosed herein. The searching operation is described herein as being implemented within a cellular communication system which uses code division multiple access (CDMA) modulation techniques. The mobile station maintains a list of an Active Set of pilot signals transmitted from base stations with which the mobile station is to communicate through, and a Neighbor Set of pilots from base stations within a predetermined proximity of the mobile station. In addition to the Neighbor and Active Sets of pilots, the mobile station maintains a list of Candidate and Pre-Candidate Sets of pilots. Based on analysis of the signal strength of the pilot signals received at the mobile station, base station entries from the Neighbor Set may be assigned to the Pre-Candidate and Candidate Sets, and eventually to the Active set. The searching operation contemplates comparing pilot signal strength measurements corresponding to each base station entry within the Neighbor Set to a first predetermined level. One or more entries from the Neighbor Set having a base station signal strength measurement greater than the first predetermined level may be placed in the Pre-Candidate Set. The strength of the pilot signals associated with entries in the Pre-Candidate Set are then further evaluated to determine eligibility within the Candidate Set, from which are selected the entries comprising the Active Set.

    14.
    发明专利
    未知

    公开(公告)号:DE60031895T2

    公开(公告)日:2007-08-30

    申请号:DE60031895

    申请日:2000-04-11

    Applicant: QUALCOMM INC

    Abstract: A method for detecting in-band interfering signals, in a wireless communication base station, the method comprising: performing downconversion and bandpass-filtering of a received analog signal to produce a downconverted bandpass-filtered analog signal which resides approximately within a predetermined reverse-link frequency band; performing automatic gain control (204) of said downconverted bandpass-filtered analog signal to produce a first gain-controlled signal whose RMS amplitude is approximately equal to a predetermined value; performing analog-to-digital conversion (208) of said first gain-controlled signal to create a stream of digital samples; performing analysis (212) of said stream of digital samples to create a first set of sub-band power measurements corresponding to the received power associated with adjacent frequency sub-bands, each sub-band representing a fraction of a predetermined spectrum analysis band, said spectrum analysis band including frequency components outside of said reverse-link frequency band; and performing spectrum evaluation (216), comprising: identifying a group of one or more adjacent sub-band power measurements which exceed a predetermined threshold; and identifying any group of one or more sub-band power measurements which is inside the reverse-link frequency band, and are less than a predetermined minimum or threshold.

    METHOD AND APPARATUS FOR REVERSE LINK OVERLOAD DETECTION

    公开(公告)号:HK1042193A1

    公开(公告)日:2002-08-02

    申请号:HK02103872

    申请日:2002-05-23

    Applicant: QUALCOMM INC

    Abstract: A detector is used to sample of set of power measurements of a receive signal. The receive signal may comprise one or more signals from remote users as well as interference. A variance of the set of power measurements is also determined. The variance is compared to an overload threshold value. If the variance exceeds the overload threshold value, for some period of time, the system is declared to be operating at a potentially unstable point. In this state, future connection originations are denied.

    16.
    发明专利
    未知

    公开(公告)号:AT218785T

    公开(公告)日:2002-06-15

    申请号:AT95944040

    申请日:1995-11-22

    Applicant: QUALCOMM INC

    Abstract: An improved method and system for performing a pilot signal searching operation in anticipation of handoff in mobile station communication between base stations is disclosed herein. The searching operation is described herein as being implemented within a cellular communication system which uses code division multiple access (CDMA) modulation techniques. The mobile station maintains a list of an Active Set of pilot signals transmitted from base stations with which the mobile station is to communicate through, and a Neighbor Set of pilots from base stations within a predetermined proximity of the mobile station. In addition to the Neighbor and Active Sets of pilots, the mobile station maintains a list of Candidate and Pre-Candidate Sets of pilots. Based on analysis of the signal strength of the pilot signals received at the mobile station, base station entries from the Neighbor Set may be assigned to the Pre-Candidate and Candidate Sets, and eventually to the Active set. The searching operation contemplates comparing pilot signal strength measurements corresponding to each base station entry within the Neighbor Set to a first predetermined level. One or more entries from the Neighbor Set having a base station signal strength measurement greater than the first predetermined level may be placed in the Pre-Candidate Set. The strength of the pilot signals associated with entries in the Pre-Candidate Set are then further evaluated to determine eligibility within the Candidate Set, from which are selected the entries comprising the Active Set.

    Method and system for detecting in-band jammers in a spread spectrum wireless base station

    公开(公告)号:AU4642700A

    公开(公告)日:2000-11-14

    申请号:AU4642700

    申请日:2000-04-11

    Applicant: QUALCOMM INC

    Abstract: A method for detecting in-band interfering signals, in a wireless communication base station, the method comprising: performing downconversion and bandpass-filtering of a received analog signal to produce a downconverted bandpass-filtered analog signal which resides approximately within a predetermined reverse-link frequency band; performing automatic gain control (204) of said downconverted bandpass-filtered analog signal to produce a first gain-controlled signal whose RMS amplitude is approximately equal to a predetermined value; performing analog-to-digital conversion (208) of said first gain-controlled signal to create a stream of digital samples; performing analysis (212) of said stream of digital samples to create a first set of sub-band power measurements corresponding to the received power associated with adjacent frequency sub-bands, each sub-band representing a fraction of a predetermined spectrum analysis band, said spectrum analysis band including frequency components outside of said reverse-link frequency band; and performing spectrum evaluation (216), comprising: identifying a group of one or more adjacent sub-band power measurements which exceed a predetermined threshold; and identifying any group of one or more sub-band power measurements which is inside the reverse-link frequency band, and are less than a predetermined minimum or threshold.

    18.
    发明专利
    未知

    公开(公告)号:BR9510068A

    公开(公告)日:1997-12-30

    申请号:BR9510068

    申请日:1995-11-22

    Applicant: QUALCOMM INC

    Abstract: An improved method and system for performing a pilot signal searching operation in anticipation of handoff in mobile station communication between base stations is disclosed herein. The searching operation is described herein as being implemented within a cellular communication system which uses code division multiple access (CDMA) modulation techniques. The mobile station maintains a list of an Active Set of pilot signals transmitted from base stations with which the mobile station is to communicate through, and a Neighbor Set of pilots from base stations within a predetermined proximity of the mobile station. In addition to the Neighbor and Active Sets of pilots, the mobile station maintains a list of Candidate and Pre-Candidate Sets of pilots. Based on analysis of the signal strength of the pilot signals received at the mobile station, base station entries from the Neighbor Set may be assigned to the Pre-Candidate and Candidate Sets, and eventually to the Active set. The searching operation contemplates comparing pilot signal strength measurements corresponding to each base station entry within the Neighbor Set to a first predetermined level. One or more entries from the Neighbor Set having a base station signal strength measurement greater than the first predetermined level may be placed in the Pre-Candidate Set. The strength of the pilot signals associated with entries in the Pre-Candidate Set are then further evaluated to determine eligibility within the Candidate Set, from which are selected the entries comprising the Active Set.

    19.
    发明专利
    未知

    公开(公告)号:FI971592A

    公开(公告)日:1997-07-22

    申请号:FI971592

    申请日:1997-04-15

    Applicant: QUALCOMM INC

    Abstract: An improved method and system for performing a pilot signal searching operation in anticipation of handoff in mobile station communication between base stations is disclosed herein. The searching operation is described herein as being implemented within a cellular communication system which uses code division multiple access (CDMA) modulation techniques. The mobile station maintains a list of an Active Set of pilot signals transmitted from base stations with which the mobile station is to communicate through, and a Neighbor Set of pilots from base stations within a predetermined proximity of the mobile station. In addition to the Neighbor and Active Sets of pilots, the mobile station maintains a list of Candidate and Pre-Candidate Sets of pilots. Based on analysis of the signal strength of the pilot signals received at the mobile station, base station entries from the Neighbor Set may be assigned to the Pre-Candidate and Candidate Sets, and eventually to the Active set. The searching operation contemplates comparing pilot signal strength measurements corresponding to each base station entry within the Neighbor Set to a first predetermined level. One or more entries from the Neighbor Set having a base station signal strength measurement greater than the first predetermined level may be placed in the Pre-Candidate Set. The strength of the pilot signals associated with entries in the Pre-Candidate Set are then further evaluated to determine eligibility within the Candidate Set, from which are selected the entries comprising the Active Set.

    Pilot signal searching technique for a cellular communications system

    公开(公告)号:AU4594596A

    公开(公告)日:1996-06-17

    申请号:AU4594596

    申请日:1995-11-22

    Applicant: QUALCOMM INC

    Abstract: An improved method and system for performing a pilot signal searching operation in anticipation of handoff in mobile station communication between base stations is disclosed herein. The searching operation is described herein as being implemented within a cellular communication system which uses code division multiple access (CDMA) modulation techniques. The mobile station maintains a list of an Active Set of pilot signals transmitted from base stations with which the mobile station is to communicate through, and a Neighbor Set of pilots from base stations within a predetermined proximity of the mobile station. In addition to the Neighbor and Active Sets of pilots, the mobile station maintains a list of Candidate and Pre-Candidate Sets of pilots. Based on analysis of the signal strength of the pilot signals received at the mobile station, base station entries from the Neighbor Set may be assigned to the Pre-Candidate and Candidate Sets, and eventually to the Active set. The searching operation contemplates comparing pilot signal strength measurements corresponding to each base station entry within the Neighbor Set to a first predetermined level. One or more entries from the Neighbor Set having a base station signal strength measurement greater than the first predetermined level may be placed in the Pre-Candidate Set. The strength of the pilot signals associated with entries in the Pre-Candidate Set are then further evaluated to determine eligibility within the Candidate Set, from which are selected the entries comprising the Active Set.

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