Patents Assigned to SIRF Technology
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Patent number: 6593897Abstract: A wireless apparatus includes an electrically conductive casing housing a ground plane and GPS receiver circuitry. The casing is electrically connected to the ground plane to form a first antenna element. The apparatus further includes a second antenna element located external the casing. The second antenna element may be configured as a wire filament in the form of a copper trace carried by a printed circuit board. The second antenna element is electrically coupled to the first antenna element and the GPS receiver circuitry. The first antenna element and second antenna element are configured and disposed relative to each other to form an antenna for receiving GPS signals.Type: GrantFiled: June 30, 2000Date of Patent: July 15, 2003Assignee: Sirf Technology, Inc.Inventor: Richard J. McConnell
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Patent number: 6577271Abstract: A signal detector is provided in which complex samples of a received signal are multiplied by data representative of a hypothesis, and the resulting product data is coherently integrated over a desired duration to provide correlation data representative of the level of correlation between the hypothesis and the signal. In one embodiment, the signal detector is part of a GPS receiver.Type: GrantFiled: March 30, 1999Date of Patent: June 10, 2003Assignee: Sirf Technology, INCInventor: Steven A. Gronemeyer
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Patent number: 6574558Abstract: A terrestrial C/A code GPS receiver system derives along-track position information while tracking as few as two GPS satellites by use of conventional altitude hold and a cross-track hold mode in which the maximum expected deviation of the vehicle from the expected track is estimated by, for example, knowledge or prediction of the width of the roadway or other track. To maintain accuracy, cross-track hold is alternated with clock hold to update the cross-track estimate when changes in vehicle direction are detected or when a predetermined period has elapsed.Type: GrantFiled: May 24, 2002Date of Patent: June 3, 2003Assignee: Sirf Technology, Inc.Inventor: Sanjai Kohli
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Patent number: 6542823Abstract: The present invention discloses a GPS system that can operate in different modes depending on the network facilities and bandwidth available, the GPS information that can be acquired, or user or system requirements. The modes comprise standalone mode, where a mobile communications device computes the position of the device, an autonomous mode, where the mobile communications device transmits the computed position to a server, application, or PSAP in a communications network, a network aided mode, where the network aides the mobile communications device in deter mg the position of the device, a network based mode, and other modes.Type: GrantFiled: April 19, 2002Date of Patent: April 1, 2003Assignee: SiRF Technology, Inc.Inventors: Lionel Jacques Garin, Kanwar Chadha, Gregory Bret Turetzky, Ashutosh Pande
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Patent number: 6539304Abstract: A GPS receiver includes a satellite receiver/processor having an input that receives input signals from at least one GPS satellite. The output of the receiver/processor provides satellite-related navigation information. A neural network receives the satellite-related information to obtain an output signal representative of receiver-related navigation information. The neural network includes a first node layer connected to a second node layer through a first connection layer and a third node layer connected to the second node layer through a second connection layer. Each of the node layers comprises a plurality of neurons.Type: GrantFiled: November 2, 2001Date of Patent: March 25, 2003Assignee: SiRF Technology, Inc.Inventor: Mangesh M. Chansarkar
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Patent number: 6531982Abstract: A system is provided for communicating location and other related information of a field unit to a remote base station. The field unit generates position signals based on signals received from communication with a plurality of GPS satellites. These position signals are transmitted to a remote base station, where they are processed and displayed. The field unit includes an environmental circuit having devices for determining an environmental condition and producing an environmental signal representative of the environmental condition. The environmental signal is also transmitted to the remote base station for processing and display. The field unit is also provided with a cellular link circuit for transmitting the position signals and the environmental signal to the remote base station via a cellular link.Type: GrantFiled: September 30, 1997Date of Patent: March 11, 2003Assignee: SiRF Technology, Inc.Inventors: Stanley A. White, Kenneth S. Walley, James W. Johnston, P. Michael Henderson, Kelly H. Hale, Warner B. Andrews, Jr., Jonathan I. Siann
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Patent number: 6529829Abstract: The present invention discloses methods, apparatuses, and systems for eliminating auto- and cross-correlation in weak signal CDMA systems, such as GPS systems. The invention uses parallel data paths that allow standard correlation of signals in parallel with verification of the lock signal to determine whether the system has locked onto the proper signal within the scanned signal window. The invention can be made with multiple CPUs, a single CPU with dual input modes, on multiple IC chips, or as a single IC chip solution for small, low cost reception, downconversion, correlation, and verification systems.Type: GrantFiled: July 20, 2001Date of Patent: March 4, 2003Assignee: SIRF Technology, Inc.Inventors: Gregory Bret Turetzky, Charles P. Norman, Henry D. Falk
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Patent number: 6526322Abstract: 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: December 16, 1999Date of Patent: February 25, 2003Assignee: SiRF Technology, Inc.Inventors: Leon Kuo-Liang Peng, Henry D. Falk
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Patent number: 6522682Abstract: A spread spectrum receiver processes signals from a plurality of sources modulated by different spread spectrum codes by sampling the signals as received to produce an integer series of sampling segments at a sampling rate at least twice a chip rate of the codes, each sampling segment containing an integer number of bits representing a fraction of a chip of the codes, time division multiplexing each sample segment into a number of channels, correlating the bits in each sample segment in each channel in parallel with a source specific series of locally generated sequential code samples differing by one bit, summing each parallel correlation, and accumulating the summed parallel correlations for each code sample in each channel at at least the chip rate to derive data related to each of the sources.Type: GrantFiled: March 2, 1999Date of Patent: February 18, 2003Assignee: SiRF Technology, Inc.Inventors: Sanjai Kohli, Steven Chen
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Patent number: 6519277Abstract: A mobile wireless transceiver selects one of multiple nearby base stations to facilitate communication over a wireless network. Each base station transmits a pilot signal that includes a spreading signal transmitted at one of many possible phase offsets. The wireless transceiver selects an initial one of the possible phase offsets of the spreading signal and then correlates a received signal against the spreading signal at consecutive ones of the possible phase offsets. Correlation begins at the selected initial phase offset and continues until a component of the received signal and the spreading signal are aligned, indicating the detection of the pilot signal from one of the base stations.Type: GrantFiled: October 16, 2001Date of Patent: February 11, 2003Assignee: SiRF Technology, Inc.Inventor: Donald Brian Eidson
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Patent number: 6519466Abstract: The present invention discloses a GPS system that can operate in different modes depending on the network facilities and bandwidth available, the GPS information that can be acquired, or user or system requirements. The modes comprise standalone mode, where a mobile communications device computes the position of the device, an autonomous mode, where the mobile communications device transmits the computed position to a server, application, or PSAP in a communications network, a network aided mode, where the network aides the mobile communications device in determining the position of the device, a network based mode, and other modes.Type: GrantFiled: February 5, 2002Date of Patent: February 11, 2003Assignee: Sirf Technology, Inc.Inventors: Ashutosh Pande, Lionel Jacques Garin, Kanwar Chadha, Gregory Bret Turetzky
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Publication number: 20030011512Abstract: The present invention discloses methods, apparatuses, and systems for eliminating auto- and cross-correlation in weak signal CDMA systems, such as GPS systems. The invention uses parallel data paths that allow standard correlation of signals in parallel with verification of the lock signal to determine whether the system has locked onto the proper signal within the scanned signal window. The invention can be made with multiple CPUs, a single CPU with dual input modes, on multiple IC chips, or as a single IC chip solution for small, low cost reception, downconversion, correlation, and verification systems.Type: ApplicationFiled: September 16, 2002Publication date: January 16, 2003Applicant: SiRF Technology, Inc.Inventors: Gregory Bret Turetzky, Charles P. Norman, Henry D. Falk
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Publication number: 20020190896Abstract: The present invention discloses a GPS system that uses call-processor intelligence to determine the mode of operation of a GPS receiver located in a GPS terminal. The modes are selected based on the availability of network facilities, the GPS information that can be acquired, or user input requirements.Type: ApplicationFiled: August 7, 2002Publication date: December 19, 2002Applicant: SiRF Technology, Inc. and Matsushita Electric Works, Ltd.Inventors: Ikuo Tsujimoto, Junichi Suzuki, Chiayee Steve Chang, Lionel Jacques Garin, Ashutosh Pande
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Patent number: 6496145Abstract: A signal detector is provided in which complex samples of a received signal are multiplied by data representative of a hypothesis, and the resulting product data is coherently integrated over a desired duration to provide correlation data representative of the level of correlation between the hypothesis and the signal. In one embodiment, the signal detector is part of a GPS receiver.Type: GrantFiled: October 4, 2001Date of Patent: December 17, 2002Assignee: SiRF Technology, Inc.Inventor: Steven A. Gronemeyer
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Publication number: 20020183076Abstract: The present invention discloses a GPS system that can operate in different modes depending on the network facilities and bandwidth available, the GPS information that can be acquired, or user or system requirements. The modes comprise standalone mode, where a mobile communications device computes the position of the device, an autonomous mode, where the mobile communications device transmits the computed position to a server, application, or PSAP in a communications network, a network aided mode, where the network aides the mobile communications device in determining the position of the device, a network based mode, and other modes.Type: ApplicationFiled: July 12, 2002Publication date: December 5, 2002Applicant: SiRF Technology, Inc.Inventors: Ashutosh Pande, Lionel Jacques Garin, Kanwar Chadha, Gregory B. Turetzky
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Patent number: 6480150Abstract: An autonomous Hardwired Tracking Loop (HWTL) ASIC comprising a HWTL coprocessor provided for implementing most of the receiver processing function for data acquisition and tracking functions of a radio receiver system in dedicated hardware. With the expanded functionality provided by an HWTL coprocessor in the autonomous HWTL ASIC, the interruption of CPU performing the navigation processing is significantly reduced to thereby maximize throughput and minimize power burden on the microprocessor. In the preferred embodiment, the HWTL ASIC also comprises the CPU and a correlator, wherein the correlator provides the high rate greater than approximately 1 KHz signal processing operations, the HWTL coprocessor providing the data acquisition and tracking (medium frequency signal processing) operations, and the CPU thereby freed to provide more bandwidth for lower frequency processing, i.e.Type: GrantFiled: May 31, 2001Date of Patent: November 12, 2002Assignee: SiRF Technology, Inc.Inventors: Henry D. Falk, Leon Kuo-Liang Peng, Wesley F. Marumo
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Patent number: 6466161Abstract: The present invention discloses methods, apparatuses, and systems for eliminating auto- and cross-correlation in weak signal CDMA systems, such as GPS systems. The invention uses parallel data paths that allow standard correlation of signals in parallel with verification of the lock signal to determine whether the system has locked onto the proper signal within the scanned signal window. The invention can be made with multiple CPUs, a single CPU with dual input modes, on multiple IC chips, or as a single IC chip solution for small, low cost reception, downconversion, correlation, and verification systems.Type: GrantFiled: July 20, 2001Date of Patent: October 15, 2002Assignee: SIRF Technology, Inc.Inventors: Gregory Bret Turetzky, Charles P. Norman, Henry D. Falk
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Patent number: 6466612Abstract: A GPS receiver system determines the presence of trackable signals at code delays less than the prompt delay being tracked for a particular signal and changes the prompt delay to correspond to the smallest code delay having a trackable signal. Trackable signals at large code delays are multipath signals and may be separately tracked to aid in dead reckoning. The trackable signals at code delays not adjacent to the currently tracked prompt delay may be tracked in the same channel as the prompt delay so that all satellite channels are continuously evaluated for multipath signals being tracked or a non-satellite specific channel may be used to sequentially step through the satellite signals to evaluate multipath on a satellite by satellite basis.Type: GrantFiled: February 6, 2001Date of Patent: October 15, 2002Assignee: SiRF Technology, Inc.Inventors: Sanjai Kohli, Charles R. Cahn
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Publication number: 20020145560Abstract: The present invention discloses a GPS system that uses call-processor intelligence to determine the mode of operation of a GPS receiver located in a GPS terminal. The modes are selected based on the availability of network facilities, the GPS information that can be acquired, or user input requirements.Type: ApplicationFiled: April 5, 2001Publication date: October 10, 2002Applicant: SiRF Technology, Inc.Inventors: Ikuo Tsujimoto, Junichi Suzuki, Chiayee Steve Chang, Lionel Jacques Garin, Ashutosh Pande
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Patent number: 6462708Abstract: The present invention discloses a GPS system that uses call-processor intelligence to determine the mode of operation of a GPS receiver located in a GPS terminal. The modes are selected based on the availability of network facilities, the GPS information that can be acquired, or user input requirements.Type: GrantFiled: April 5, 2001Date of Patent: October 8, 2002Assignees: Sirf Technology, Inc., Matsushita Electric Works, Ltd.Inventors: Ikuo Tsujimoto, Junichi Suzuki, Chiayee Steve Chang, Lionel Jacques Garin, Ashutosh Pande