Patents Assigned to SiRF Technology, Inc.
-
Publication number: 20130072122Abstract: Systems and methods for channel pairing a transmitter and a receiver are provided. In this regard, a representative method, among others, includes selecting a channel in a radio frequency (RF) band; transmitting a carrier and alert tone on the selected channel in the RF band; responsive to detecting the transmitted carrier and alert tone, demodulating the carrier and alert tone on the selected channel in the RF band and producing the demodulated alert tone; and responsive to detecting the produced alert tone, using the selected channel to establish a wireless link between the transmitter and receiver.Type: ApplicationFiled: November 14, 2012Publication date: March 21, 2013Applicant: SIRF Technology, Inc.Inventor: SIRF Technology, Inc.
-
Publication number: 20130021202Abstract: Provided herein are methods and systems for efficient communication between a server and a client in an assisted navigation system. In one or more embodiments, the server transmits a set of parameters for a satellite to the client, e.g., a GPS receiver, via a wireless or wired connection. The set of parameters includes a force parameter, initial condition parameters and time correction coefficients for the satellite. The receiver uses the received parameters in a numerical integration to compute the position of the satellite at a desired time. The set of parameters needed for the integration is small. To further reduce the amount of data transmitted, reference parameters may be subtracted from the original parameters before transmission from the server. The receiver is able to reconstruct the original parameters from the received parameters and the identically computed reference parameters. The parameters may be further compressed using data compression techniques.Type: ApplicationFiled: August 1, 2012Publication date: January 24, 2013Applicants: SIRF TECHNOLOGY, INC.Inventors: Shaowei HAN, Wentao ZHANG
-
Publication number: 20120274427Abstract: A Radio Frequency Receiver on a Single Integrated Circuit (“RFSIC”) is described. The RFSIC may include a mixer, a phase-locked loop (“PLL”) in signal communication with the mixer, and an on-chip auto-tuned RF filter in signal communication with both the mixer and PPL, such that the same PLL simultaneously tunes the frequency of the VCO and the frequency response of the auto-tuned RF filter.Type: ApplicationFiled: October 28, 2011Publication date: November 1, 2012Applicant: SiRF Technology Inc.Inventors: Noshir Dubash, Jeffrey E. Koeller, Daniel Babitch
-
Patent number: 8260540Abstract: Provided herein are methods and systems for efficient communication between a server and a client in an assisted navigation system. In one or more embodiments, the client, e.g., a GPS receiver, receives a set of parameters for a satellite from the server via a wireless or wired connection. The set of parameters includes a force parameter, initial condition parameters and time correction coefficients for the satellite. The receiver uses the received parameters in a numerical integration to compute the position of the satellite at a desired time. The set of parameters needed for the integration is small compared to current methods which require sending more data to the client. Thus these parameters require less communication resources to transmit. To further reduce the amount of data that needs to be transmitted, reference parameters may be subtracted from the original parameters before transmission from the server.Type: GrantFiled: June 2, 2009Date of Patent: September 4, 2012Assignee: Sirf Technology, Inc.Inventors: Shaowei Han, Wentao Zhang
-
Publication number: 20120191614Abstract: A system for improving transaction security based on location information. The system includes a transaction processing center in communication with a first transaction device and a second transaction device. The transaction processing center includes a receiver that receives respective identification and location from at least one of the first and second transaction devices. The transaction processing center also includes a transaction processor that validates the identifications, validates the locations, and executes a transaction between the first and second transaction devices when the identifications and locations are validated.Type: ApplicationFiled: January 20, 2011Publication date: July 26, 2012Applicant: SiRF Technology Inc.Inventors: Daniel Babitch, Lionel Garin
-
Publication number: 20120182183Abstract: A GPS receiver for tracking a GPS signal. The receiver generates a mixed GPS signal by mixing the GPS signal with an oscillator signal, generates a first correlation signal by correlating the mixed GPS signal with a reference signal, and generates a filtered GPS signal from the GPS signal. The receiver also generates a filtered reference signal from the reference signal, generates a second correlation signal by correlating the filtered GPS signal with the filtered reference signal, and a generates a combined correlation signal by combining the first correlation signal with the second correlation signal. The receiver tracks the GPS signal by adjusting the phase of the oscillator signal based on the combined correlation signal.Type: ApplicationFiled: January 19, 2011Publication date: July 19, 2012Applicant: SiRF Technology Inc.Inventor: Nam Dieu Banh
-
Patent number: 8218766Abstract: Systems and methods are provided to facilitate transactions or limit operations. According to one embodiment, region information is determined in accordance with information received by a user device from a local location device. A region requirement is also determined, and it is arranged for the user device to operate in accordance with the region information and the region requirement.Type: GrantFiled: October 16, 2002Date of Patent: July 10, 2012Assignee: Sirf Technology, Inc.Inventor: Anant Sahai
-
Patent number: 8151170Abstract: Systems and methods are disclosed herein for improving the sensitivity of satellite data decode in a satellite navigation receiver. The low signal ephemeris data decoding system of the present disclosure achieves a 5 db improvement in decoding sensitivity over conventional system by operating down to a CN0 of 21 dB-Hz. The improved sensitivity is achieved through a combination of reducing the number of data bits to be decoded, overcoming the inherent differential decoding problem of an all data bit polarity inversion, improving the probability of seeing single bit decoding error in an ephemeris word, running the parity correction algorithm, and reducing the undetected word error rate. The improved sensitivity makes it possible to predict the orbit of the satellite and to determine the receiver's location with higher accuracy even when operating in challenging signal conditions.Type: GrantFiled: December 2, 2008Date of Patent: April 3, 2012Assignee: Sirf Technology, Inc.Inventors: Gary Lennen, William Kerry Keal
-
Patent number: 8134502Abstract: Systems and methods are disclosed to use adaptive continuous tracking (ACT) to reduce the power consumption of GNSS receivers. In GNSS receivers, a longer observation time of the satellites translates into better positioning accuracy but also consumes more power. ACT allows satellite observation time to be tuned to the desired positioning performance by dynamically adjusting the on time period of the receivers while maintaining a minimum performance metric. The performance metric may be formed from a combination of the estimated position error, the horizontal dilution of precision (HDOP), the data collection state, and the receiver operating environment as characterized by the carrier to noise ratio (CN0).Type: GrantFiled: August 13, 2009Date of Patent: March 13, 2012Assignee: SIRF Technology, Inc.Inventor: Gary Lennen
-
Patent number: 8111791Abstract: A method for designing a digital filter, includes: (a) selecting a predetermined number of current sets of coefficients for the digital filter; (b) selecting a metric for evaluating coefficients of the digital filter; (c) computing a metric for each current set of coefficients; (d) deriving a next set of coefficients based on a subset of the current set of coefficients; (e) computing the metric for the next set of coefficients; (f) replacing a selected one of the current set of coefficients based on comparing the metric for the next set of coefficients with the metric for the selected current set of coefficients; and (g) iterating steps (a) to (e) until a termination criterion is met. In one embodiment, the selected metric represents a desired stop band response. The next set of coefficients may be derived by adjusting a first current set of coefficients by a weighted difference between a second current set of coefficients and a third current set of coefficients.Type: GrantFiled: December 20, 2006Date of Patent: February 7, 2012Assignee: SiRF Technology, Inc.Inventor: Mark Alan Sturza
-
Patent number: 8103289Abstract: A system is described that utilizes the measured characteristics of a cell site or a plurality of cell sites (100, 102, 104) and the cellular identification to selectively provide a wireless device (118) with location aiding from a cellular network server (120). The system may include a basestation (106, 108, 110) located within the cell site, a cellular measurement unit located in the wireless device (118), and a database (214) containing positional assistance information corresponding to the characteristic information. The system may also include a processing unit in signal communication with the basestation and the database (214) and a positional determination unit in the wireless device (118).Type: GrantFiled: May 20, 2011Date of Patent: January 24, 2012Assignee: SIRF Technology, Inc.Inventors: Ashutosh Pande, Lionel Jacques Garin
-
Patent number: 8098765Abstract: Methods and systems for processing a Global Positioning System (GPS) signal are provided. A method includes: transforming a time domain GPS signal to a frequency domain GPS signal; storing a frequency domain pseudorandom noise (PRN) signal; correlating the frequency domain GPS signal with the PRN signal at a plurality of frequencies, said correlating including: shifting the frequency domain GPS signal by an amount corresponding to one of the plurality of frequencies; downsampling the shifted frequency domain GPS signal; and multiplying the shifted frequency domain GPS signal by the stored frequency domain PRN signal to produce a correlated signal.Type: GrantFiled: February 23, 2005Date of Patent: January 17, 2012Assignee: SIRF Technology, Inc.Inventors: Paul Eric Beckmann, Andrew Chou, Julien Basch
-
Publication number: 20120007572Abstract: A voltage converter includes a power switch having respective charging and discharging control terminals, and an output terminal coupled to a series connected inductor and capacitor. The voltage converter also includes a charging switch coupled to the charging control terminal of the power switch, a discharging switch coupled to the discharging control terminal of the power switch, and a feedback circuit coupling the power switch, charging switch and discharging switch to a node at which the capacitor and inductor are connected. During a charging phase, the charging switch couples the capacitor to the charging control terminal of the power switch, and during a discharging phase, the discharging switch couples the capacitor to the discharging control terminal of the power switch.Type: ApplicationFiled: July 6, 2010Publication date: January 12, 2012Applicant: SiRF Technology Inc.Inventor: Ludovic Oddoart
-
Publication number: 20110316741Abstract: Control and feature systems for processing signals from a satellite positioning system include an expert system receiver manager; a joint detection, carrier centering and bit sync acquisition subsystem; peak detection; a multi-dimensional measurement interpolation subsystem; a system for mode switching between a navigational signal; and power control module for receiver.Type: ApplicationFiled: July 29, 2011Publication date: December 29, 2011Applicant: SiRF Technology Inc.Inventors: Mangesh Chansarkar, Sundar Raman, Charles P. Norman, Paul A. Underbrink, Henry D. Falk, James Brown, Robert Harvey, Peter Michali, Williams Higgins, Gensheng Zhang, Qingwen Zhang
-
Publication number: 20110312336Abstract: A satellite based positioning method and system including storing satellite sub-almanac data on a mobile station. Embodiments include using the sub-almanac data to take measurements and calculate a coarse position of the mobile station. Embodiments further include a location server calculating a correction to the coarse position, and the location server determining whether any sub-almanacs used to calculate the coarse position require replacement.Type: ApplicationFiled: July 30, 2010Publication date: December 22, 2011Applicant: SiRF Technology Inc.Inventors: Lionel Jacques Garin, Kurt Christian Schmidt
-
Patent number: 8078189Abstract: In a method for providing location-based information over a network, a plurality of GPS reference data sets, corresponding to a plurality of respective local areas, are acquired at intervals such that each GPS reference data set is updated on a continuous basis. A plurality of aiding data sets are generated at intervals based on the respective GPS data sets, whereby each aiding data set is updated on a continuous basis. The generated aiding data sets are stored at intervals on a data-storing network server, whereby updated aiding data sets are available on a continuous basis for access by a requesting entity via communication with the data-storing network server.Type: GrantFiled: March 24, 2005Date of Patent: December 13, 2011Assignee: Sirf Technology, Inc.Inventors: Steve Chang, Ashutosh Pande, Lionel Jacques Garin, Kanwar Chadha, Leon Kuo-Liang Peng, Gengsheng Zhang, Nicolas Patrick Vantalon, Gregory Turetzky
-
Patent number: 8072376Abstract: A positioning system receiver that mitigates cross correlation of received signals from positioning system satellite vehicles by generating the strong satellite vehicle signal and subtracting it from the received signal before correlation while eliminating the need for cross correlation signature without changing the C/A code.Type: GrantFiled: December 19, 2008Date of Patent: December 6, 2011Assignee: SiRF Technology Inc.Inventor: Gary Lennen
-
Patent number: 8073414Abstract: A Radio Frequency Receiver on a Single Integrated Circuit (“RFSIC”) is described. The RFSIC may include a mixer, a phase-locked loop (“PLL”) in signal communication with the mixer, and an on-chip auto-tuned RF filter in signal communication with both the mixer and PPL, such that the same PLL simultaneously tunes the frequency of the VCO and the frequency response of the auto-tuned RF filter.Type: GrantFiled: December 22, 2008Date of Patent: December 6, 2011Assignee: SiRF Technology Inc.Inventors: Noshir Dubash, Jeffrey E. Koeller, Daniel Babitch
-
Patent number: 8069314Abstract: A shared memory architecture for a GPS receiver, wherein a processing memory is shared among the different processing functions, such as the correlator signal processing, tracking processing, and other applications processing. The shared memory architecture within the GPS receiver provides the memory necessary for signal processing operations, such as the massively parallel processing, while conserving memory cost by re-using that same memory for other GPS and non-GPS applications. The shared memory architecture for a GPS receiver provided in accordance with the principles of this invention thereby significantly minimize the costly memory requirement often required of extremely fast signal acquisition of a GPS receiver.Type: GrantFiled: July 18, 2005Date of Patent: November 29, 2011Assignee: SiRF Technology, Inc.Inventors: Leon Kuo-Liang Peng, Henry D. Falk
-
Publication number: 20110279318Abstract: A system and method capable of mitigating the migration from the current GPS system to the Galileo system and allow a single satellite system positioning receiver to process both GPS signals and Galileo signals.Type: ApplicationFiled: July 8, 2011Publication date: November 17, 2011Applicant: SiRF Technology Inc.Inventor: Gary Lennen