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106 条记录 (耗时 0.035 秒)

    SYSTEM AND METHOD TO DETERMINE THE LOCATION OF A RECEIVER
    63.
    发明授权
    SYSTEM AND METHOD TO DETERMINE THE LOCATION OF A RECEIVER 有权
    SYSTEM AND METHOD FOR的接收机的确定位置

    公开(公告)号：EP1419401B1

    公开(公告)日：2009-08-12

    申请号：EP02783975.2

    申请日：2002-09-07

    申请人： SiRF Technology, Inc.

    发明人： SAHAI, Anant ,  CHOU, Andrew

    IPC分类号： G01S1/04

    CPC分类号： G01S19/29 ,  G01S19/09 ,  G01S19/22 ,  G01S19/30

    摘要： System and method to determine the location of a receiver are provided. The received signal is decomposed into signal chunks that are then correlated with the reference signals of the transmitting sources. In some embodiments, the signal chunks may be shorter than the period of the reference signals. For each signal source, a grid of correlation values is constructed containing one column of correlation values for each signal chunk. Each column contains correlation values for several code-phases. Probes are executed in the grid to acquire the location-determining signals. In some embodiments, a probe includes calculating the fourier transform of a row in the grid, yielding correlation values associated with a refined set of frequency values. Potential acquisitions are verified by processing increasing portions of the received signal. Confirmed acquisition may be used to aid further acquisitions. Some embodiments eventually compress the received signal down to a one period duration by means of an ultra-stacking method. Additional verification, comprising multi-peak tests and multi-path tests, may be performed on the correlation magnitude curve obtained from the ultra- stacked signal. Finally, refined code-phase values are extracted from these correlation magnitude curves.

    CONTROL OF POWER CONSUMPTION IN SATELLITE POSITIONING SYSTEMS
    64.
    发明授权
    CONTROL OF POWER CONSUMPTION IN SATELLITE POSITIONING SYSTEMS 有权
    控制卫星定位系统功率利用

    公开(公告)号：EP1654556B9

    公开(公告)日：2009-08-05

    申请号：EP04786118.2

    申请日：2004-07-27

    申请人： SiRF Technology, Inc.

    发明人： TSO, Robert ,  GRONEMEYER, Steve

    IPC分类号： G01S1/00

    CPC分类号： H04W88/02 ,  G01S19/34 ,  H04B1/16 ,  H04W52/0225 ,  H04W52/028

    摘要： An interface between an RF processing section and a baseband processing section supports general purpose message transmission as well as satellite positioning system signal sample transmission between the RF processing section and the baseband processing section. The interface includes a bi-directional message interface and a data interface. The message interface supports transmission of power control messages to the RF processing section to provide detailed control over activation or de-activation of individual blocks of hardware circuitry in the RF processing section.

    DETERMINING LOCATION INFORMATION FROM SAMPLED POSITIONING SIGNALS
    65.
    发明授权
    DETERMINING LOCATION INFORMATION FROM SAMPLED POSITIONING SIGNALS 有权
    测定本地信息采样定位信号

    公开(公告)号：EP1449005B1

    公开(公告)日：2009-03-25

    申请号：EP02752163.2

    申请日：2002-06-21

    申请人： SiRF Technology, Inc.

    发明人： SAHAI, Anant ,  TSITSIKLIS, John ,  VAN ROY, Benjamin ,  CHOU, Andrew ,  MANN, Wallace ,  STONE, Jesse, R. ,  FONG, WungKum

    IPC分类号： G01S1/04

    CPC分类号： G01S19/30

    摘要： According to one aspect of the invention, sampled data that is received from a receiver is divided into segments of data of increasing length. A current value range for a delay value and a current value range for a modulation frequency value are calculated relative to each signal source from a set of signal sources that are overhead the signal receiver. An estimate for the delay value and an estimate for the modulation frequency value are calculated by iteratively updating the current value range for the delay value and for the modulation frequency value. The iterative update of the current value range for the delay value and for the modulation frequency value is performed overthe set of signal sources and over the segments of data of increasing length. According to another aspect of the technique, for each signal source, I and Q correlation integrals and their magnitude value are calculated corresponding to the estimate of the modulation frequency value and the estimate of the delay value. In addition, for each signal source, I and Q correlation integrals and thier magnitude values are calculated corresponding to a set of delay values that surround the estimate of the delay value. A shape of a magnitude-curve is interpolated using the magnitude values corresponding to the estimate of the delay value and corresponding to the set of delay values that surround the estimate of the delay value. The location of the receiver is calculated using the shape of the magnitude-curve to represent the I and Q correlation integrals for each signal source.

    CALIBRATED REAL TIME CLOCK FOR ACQUISITION OF GPS SIGNALS DURING LOW POWER OPERATION
    66.
    发明授权
    CALIBRATED REAL TIME CLOCK FOR ACQUISITION OF GPS SIGNALS DURING LOW POWER OPERATION 有权
    校准的实时时钟，用于采集GPS信号期间，低功耗运行

    公开(公告)号：EP1451605B1

    公开(公告)日：2008-12-10

    申请号：EP02776367.1

    申请日：2002-10-30

    申请人： SiRF Technology, Inc.

    发明人： GRONEMEYER, Steven, A.

    IPC分类号： G01S3/16 ,  G06F1/14 ,  G06F1/32 ,  H03L1/02

    CPC分类号： G04G19/12 ,  G01S19/23 ,  G01S19/235 ,  G01S19/34 ,  G04C10/04 ,  G04F5/00 ,  G06F1/14 ,  G06F1/3203 ,  Y02D10/126

    摘要： Power is conserved in a Global Positioning System (GPS) receiver by shutting down selected components during periods when the GPS receiver is not actively calculating the GPS receiver location. A low power time keeping circuit accurately preserves GPS time when the selected components are deactivated. When the selected components are turned on in response to a wake-up command, time provided from the low power time keeping circuit, corrected for actual operating temperatures, and data from the GPS clock temperature/frequency table, are used to recalibrate time from a GPS oscillator. Positions of the GPS satellites are then estimated such that the real GPS time is quickly determined from the received satellite signals. Once real GPS time is determined from the detected satellite signals, the selected components are deactivated. The process described above is repeated such that accurate GPS time is maintained by the low power time keeping circuit.

    COMBINED PARALLEL AND SEQUENTIAL DETECTION FOR GPS SIGNAL ACQUISITION
    67.
    发明授权
    COMBINED PARALLEL AND SEQUENTIAL DETECTION FOR GPS SIGNAL ACQUISITION 有权
    FOR GPS信号捕获联合并行和串行检测

    公开(公告)号：EP1303766B1

    公开(公告)日：2008-08-13

    申请号：EP01948576.2

    申请日：2001-06-20

    申请人： SiRF Technology, Inc.

    发明人： NORMAN, Charles, P. ,  ROUNDS, Stephen, F.

    IPC分类号： G01S1/00 ,  H04B1/707

    CPC分类号： H04B1/70775 ,  G01S19/29 ,  G01S19/30 ,  G01S19/37 ,  H04B1/709

    摘要： A two part signal acquisition process includes a parallel signal detection process and signal verification/false alarm rejection process. A massively parallel architecture of acquisition correlators (14) search a large region of time-frequency uncertainty during the parallel signal detection process to identify the most likely detections for each search dwell. Concurrent with the parallel signal detection process performed by the acquisition correlators (14), the current list of most likely detections (16) is examined with additional search dwells in the verification/false alarm rejection process. The verification/false alarm rejection (12) process is performed by a plurality of independent correlators or tracking channels (18). Under software control, the tracking channels perform repeated dwells on the most likely detections until they can be dismissed as false alarms or verified as the desired signal.

    METHOD AND APPARATUS FOR DETECTING JAMMING SIGNAL IN A DSSS SYSTEM USING PHASE TRANSITION COUNTING
    69.
    发明授权
    METHOD AND APPARATUS FOR DETECTING JAMMING SIGNAL IN A DSSS SYSTEM USING PHASE TRANSITION COUNTING 有权
    方法和装置DETEKTIONIEREN IN A DSSS系统中的噪声信号使用相变计数

    公开(公告)号：EP1530832B1

    公开(公告)日：2006-09-13

    申请号：EP03765491.0

    申请日：2003-07-07

    申请人： SiRF Technology, Inc.

    发明人： FITZRANDOLPH, David, K.

    IPC分类号： H04B1/707 ,  H04B1/10

    CPC分类号： H04K3/228 ,  H04B1/1036 ,  H04B1/71

    摘要： In a wireless communication device (106) a method of detecting a narrowband jamming signal (404) includes receiving a wireless communication signal (104) and downconverting the wireless communication signal (104) to an intermediate frequency (IF) signal (525). IF signal (525) is digitized to provide a digital signal (527). Digital signal (527) is despread, demodulated and monitored for the number of phase transitions (562) occurring during a time interval (556). The method further includes comparing the number of phase transitions (562) during the time interval (556) with a threshold value (560) and determining that the wireless communication signal (104) is not the narrowband jamming signal (404) if the number of phase transitions (562) during the time interval (556) exceeds the threshold value (560), or determining that the wireless communication signal (104) is the narrowband jamming signal (404) if the number of phase transitions (562) during the time interval (556) is less than the threshold value (560).