Abstract: A method and apparatus for receiving a signal from transmitters such as GPS satellites, for fixing the location of the receiver. Each of the transmitted signals includes a unique periodically-repeating sequence. A received signal is stored by the receiver for at least two repetitions of the periodically-repeating sequence. FFT operations are performed, and the resulting data frequency samples are pruned responsive to a hypothesized residual frequency, a procedure which significantly reduces the total number of subsequent calculations and therefore significantly reduces processing time. A correlation series is determined from the pruned samples and reference frequency samples corresponding to a hypothesized transmitter. If a match is found in the examination of this series, a code phase offset is determined; if not the process is repeated with another hypothesized residual frequency. Multiple correlation series similarly obtained may also be incoherently combined prior to this examination.

Abstract: A method for time synchronizing base stations in an asynchronous cellular communication system via multi-communications mode user equipment is described. The method includes receiving time-of-day in a synchronous cellular communication signal with the user equipment operable in a synchronous cellular communications mode. Alternatively, time-of-day is received from a non-cellular system signal with user equipment that is operable to receive signals from the non-cellular system. After time-of-day is received the user equipment is switched to operate in an asynchronous cellular communications mode. Then a frame boundary of a received asynchronous cellular communication signal is time-tagged. Timing information is then transmitted to an entity of the asynchronous cellular communication system to determine time-of-day at the entity.

Abstract: A method and apparatus for receiving a signal from transmitters such as GPS satellites, for fixing the location of the receiver. Each of the transmitted signals includes a unique periodically-repeating sequence. A received signal is stored by the receiver for at least two repetitions of the periodically-repeating sequence. FFT operations are performed, and the resulting data frequency samples are pruned responsive to a hypothesized residual frequency, a procedure which significantly reduces the total number of subsequent calculations and therefore significantly reduces processing time. A correlation series is determined from the pruned samples and reference frequency samples corresponding to a hypothesized transmitter. If a match is found in the examination of this series, a code phase offset is determined; if not the process is repeated with another hypothesized residual frequency. Multiple correlation series similarly obtained may also be incoherently combined prior to this examination.

Abstract: A method and apparatus for processing satellite positioning system (SPS) signals which are weak in level. In one embodiment, a SPS receiver receives at least two signal samples representing, at least in part, common information, wherein the two signal samples are associated with one or more satellite messages. By combining the two signal samples, navigation information (e.g., time, position, velocity, etc.) may be determined based on the combination of the two signal samples. According to another embodiment, the two signal samples are differentially demodulated and summed together to form the combination.

Abstract: A method and apparatus for receiving a signal from transmitters such as GPS satellites, for fixing the location of the receiver. Each of the transmitted signals includes a unique periodically-repeating sequence. A received signal is stored by the receiver for at least two repetitions of the periodically-repeating sequence. FFT operations are performed, and the resulting data frequency samples are pruned responsive to a hypothesized residual frequency, a procedure which significantly reduces the total number of subsequent calculations and therefore significantly reduces processing time. A correlation series is determined from the pruned samples and reference frequency samples corresponding to a hypothesized transmitter. If a match is found in the examination of this series, a code phase offset is determined; if not the process is repeated with another hypothesized residual frequency. Multiple correlation series similarly obtained may also be incoherently combined prior to this examination.

Abstract: A method and apparatus for providing emergency notification by a wireless mobile device in response to triggering a sensor. A detection system, which may be located within a vehicle, comprises one or more sensors configured to sense an emergency event and transmit a message via a wireless link regarding the emergency event. For example, the wireless mobile device may be programmed to call a predetermined emergency number such as E911, and transmit data including position and other information from the mobile device to the emergency number in response to the received message.

Abstract: Position location signaling system, apparatus, and method are disclosed. Position location beacons can each be configured to transmit a frequency interlaced subset of orthogonal frequencies spanning substantially an entire channel bandwidth. The orthogonal frequencies can be pseudorandomly or uniformly spaced, and each beacon can be allocated an equal number of orthogonal frequencies. Each frequency of the interlaced subset of orthogonal frequencies can be modulated with an element of a predetermined data sequence. A mobile device can receive one or more of the beacon signals and determine a position using a position location algorithm that determines position in part on an arrival time of the beacon signal. Where the mobile device can receive three or more beacon signals, the mobile device can perform position location by trilateration to the beacon positions based, for example, on a time difference of arrival.

Abstract: Methods and apparatuses for establishing time at a first basestation, and synchronizing the first basestation with other basestations in a cellular network. The method may be performed using a mobile (cellular communication) station that includes a satellite position system receiver. One method comprises determining a location of the mobile station, determining a time indicator that represents a time-of-day at the mobile station, wherein the time indicator is determined relative to a signal available at the first basestation, transmitting at least one of the position information and location, and transmitting the time indicator from the mobile station. The time indicator and at least one of the position information and the location are used to establish a time at the first basestation such that the first basestation is synchronized to other basestations in the cellular communication system. Other methods and apparatuses are also described for synchronizing basestations in a cellular network.

Abstract: A method and apparatus for processing satellite positioning system (SPS) signals which are weak in level. In one embodiment, a SPS receiver receives at least two signal samples representing, at least in part, common information, wherein the two signal samples are associated with one or more satellite messages. By combining the two signal samples, navigation information (e.g., time, position, velocity, etc.) may be determined based on the combination of the two signal samples. According to another embodiment, the two signal samples are differentially demodulated and summed together to form the combination.

Abstract: Methods and apparatuses for frequency synchronizing basestations in a cellular communication system. In one aspect of the invention, a method to predict a timing of transmission of a basestation in a cellular communication system includes: receiving a first time tag for a first timing marker in a first cellular signal transmitted from the basestation; receiving a second time tag of a second timing marker in a second cellular signal transmitted from the basestation; and computing a frequency related to the basestation using the first and second time tags. Each of the time tags are determined using at least one satellite positioning system signal received at a mobile station which receives the corresponding time marker.

Abstract: A method and apparatus for receiving a signal from transmitters such as GPS satellites, for fixing the location of the receiver. Each of the transmitted signals includes a unique periodically-repeating sequence. A received signal is stored by the receiver for at least two repetitions of the periodically-repeating sequence. FFT operations are performed, and the resulting data frequency samples are pruned responsive to a hypothesized residual frequency, a procedure which significantly reduces the total number of subsequent calculations and therefore significantly reduces processing time. A correlation series is determined from the pruned samples and reference frequency samples corresponding to a hypothesized transmitter. If a match is found in the examination of this series, a code phase offset is determined; if not the process is repeated with another hypothesized residual frequency. Multiple correlation series similarly obtained may also be incoherently combined prior to this examination.

Abstract: Methods and systems are provided for allowing possible motion or lack of motion of a mobile terminal to be detected based, at least in part, on at least one wireless signal. For example, according to one method a mobile terminal may be configured to operate in a first wireless communication system and the method may include detecting motion or lack of motion of the mobile terminal based, at least in part, on at least one wireless signal from at least one terrestrial-based second wireless communication system, and in response to detecting the motion or lack of motion, initiating or stopping at least one process within the mobile terminal.

Abstract: A method and apparatus for processing satellite positioning system (SPS) signals which are weak in level. In one embodiment, a SPS receiver receives at least two signal samples representing, at least in part, common information, wherein the two signal samples are associated with one or more satellite messages. By combining the two signal samples, navigation information (e.g., time, position, velocity, etc.) may be determined based on the combination of the two signal samples. According to another embodiment, the two signal samples are differentially demodulated and summed together to form the combination.

Abstract: A method and apparatus for providing emergency notification by a wireless mobile device in response to triggering a sensor. A detection system, which may be located within a vehicle, comprises one or more sensors configured to sense an emergency event and transmit a message via a wireless link regarding the emergency event. For example, the wireless mobile device may be programmed to call a predetermined emergency number such as E911, and transmit data including position and other information from the mobile device to the emergency number in response to the received message.

Abstract: A method and apparatus for providing emergency notification by a wireless mobile device in response to triggering a sensor. A detection system, which may be located within a vehicle, comprises one or more sensors configured to sense an emergency event and transmit a message via a wireless link regarding the emergency event. For example, the wireless mobile device may be programmed to call a predetermined emergency number such as E911, and transmit data including position and other information from the mobile device to the emergency number in response to the received message.

Abstract: A mobile system, such as a wireless phone, communicates its location or other position information, such as pseudoranges, to a server system and optionally sends permission criteria defining which other mobile systems are allowed to access its location. In the case where the mobile system does not provide its location, the server determines the location using the other position information provided (e.g. pseudoranges for satellites in view of the mobile system). The server system sends the location to other mobile systems in accordance with the permission criteria, with or without a request from another mobile system for the location. If no permission criteria has been sent by the mobile system, the server system queries the mobile system for the permission criteria in response to a request for the location. If no permission criteria is sent by the mobile system, or if the permission criteria sent denies the request, the server system can, alternately, not reply to the request or reply with an error message.

Abstract: Methods and apparatuses for determining a position of a mobile satellite positioning system (SPS) receiver which is coupled to a communication receiver or transceiver. In one exemplary method, a change in a communication signal received by the communication receiver is determined. A parameter, based on the change, is determined, and SPS signals from SPS satellites are processed according to the parameter. According to further details of this method, the change involves the fluctuation of the level of the communication signal and the parameter is a motion information which specifies a frequency range for searching for SPS signals in the process of acquiring the SPS signals from SPS satellites. In an alternative embodiment the change in the communication signal is a change in the transmitted signal in response to power control commands. Apparatuses, such as a mobile communication system which includes an SPS receiver and a communication receiver, are also described.

Abstract: Methods and apparatuses for determining a position of a mobile satellite positioning system (SPS) receiver which is coupled to a communication receiver or transceiver. In one exemplary method, a change in a communication signal received by the communication receiver is determined. A parameter, based on the change, is determined, and SPS signals from SPS satellites are processed according to the parameter. According to further details of this method, the change involves the fluctuation of the level of the communication signal and the parameter is a motion information which specifies a frequency range for searching for SPS signals in the process of acquiring the SPS signals from SPS satellites. In an alternative embodiment the change in the communication signal is a change in the transmitted signal in response to power control commands. Apparatuses, such as a mobile communication system which includes an SPS receiver and a communication receiver, are also described.

Abstract: Methods and systems for frequency synchronizing base stations in a cellular communication system. In one aspect of the invention, a method to measure a frequency related to a base station of a cellular communication system includes receiving a satellite positioning system signal; determining a frequency of a reference signal from a local oscillator of a mobile station from the satellite position system signal; receiving a first cellular signal from a base station containing first and second timing markers; determining first and second time tags for the markers using the reference signal; and combining the frequency of the reference signal and the first and second time tags to compute a first frequency related to the base station.

Abstract: Methods and apparatuses for frequency synchronizing basestations in a cellular communication system. In one aspect of the invention, a method to predict a timing of transmission of a basestation in a cellular communication system includes: receiving a first time tag for a first timing marker in a first cellular signal transmitted from the basestation; receiving a second time tag of a second timing marker in a second cellular signal transmitted from the basestation; and computing a frequency related to the basestation using the first and second time tags. Each of the time tags are determined using at least one satellite positioning system signal received at a mobile station which receives the corresponding time marker.