摘要:
A global navigation satellite system (GNSS) enabled mobile device comprising a crystal oscillator and an automatic frequency correction (AFC) circuit may be operable to share the crystal oscillator between processing of cellular radio signals and processing of GNSS data messages. The GNSS enabled mobile device may be operable to enforce an AFC correction when the crystal oscillator drifts beyond a specific frequency error. The AFC correction may be allowed during time intervals corresponding to GNSS words at which decoding of these words is not required. The GNSS enabled mobile device may be operable to disable the AFC correction during time intervals associated with decoding of words while the crystal oscillator may drift within the specific frequency error range. After the decoding of one or more of words is completed, the AFC correction may be allowed during the time intervals corresponding to these words.
摘要:
A method and apparatus for mitigating interference in a satellite signal receiver is described. The satellite signal receiver receives satellite signals from a plurality of satellites. In one example, a control signal is transmitted to the satellite signal receiver upon occurrence of data transmission from a wireless transceiver operating in proximity to the satellite signal receiver. Signal integration within the satellite signal receiver is gated in response to the control signal. In another example, one or more values of satellite signal samples are selected from a plurality of possible values. Signal integration within the satellite signal receiver is gated in response to a percentage of satellite signal samples taken over a predefined period exceeding a predefined threshold. In yet another example, a gain setting of an automatic gain control circuit within the satellite signal receiver is adjusted in response to detection of interference.
摘要:
Method and apparatus for locating position of a mobile device in an assisted satellite positioning system is described. In one example, satellite measurement data is obtained from a plurality of satellites at a mobile device. Position of the mobile device is computed using the satellite measurement data. The position is sent to a cellular device via a wireless ad hoc network. In one example, the wireless ad hoc network comprises a BLUETOOTH communication link. In one example, the mobile device is configured to receive assistance data from a position server through the wireless ad hoc network. For example, the mobile device may comprise a housing configured to plug into a cigarette lighter connector of an automobile and the cellular device may comprise a cellular telephone without location-determination capabilities (i.e., the cellular telephone does not include an integrated GPS receiver).
摘要:
Methods and systems for measuring wireless signals are described. The method includes generating a velocity estimate that includes a speed and a direction of a wireless receiver. A change in the velocity estimate is detected and how frequently the wireless signal is measured is adjusted according to the change detected in the velocity estimate. Systems may include wireless receivers that include an accelerometer that is operable to generate a velocity estimate that includes speed and direction of the wireless receiver. The wireless receivers may also include a processor operable to adjust a measurement period of the wireless signal in the wireless receiver according to a rate of change in the velocity estimate.
摘要:
Aspects of a method and system for communication are provided. In this regard, a femtocell may receive messages from a plurality of different sources comprising one or more other femtocells, one or more cellular enabled communication devices, and one or more non-cellular network nodes. The femtocell may select, based on the received messages, a master clock within one of the plurality of different sources as a master clock for synchronization of the plurality of different sources. A femtocell clock, a global navigational satellite signal (GNSS) clock, a cellular base station clock, or a cellular enabled communication device clock may be selected as the master clock. The femtocell may transmit and/or receive synchronization messages to and/or from the one or more cellular enabled communication devices and the one or more non-cellular network nodes.
摘要:
A communication device within a GNSS group propagates GNSS assistance data to one or more other communication devices in the GNSS group utilizing direct device-to-device connections. The GNSS assistance data comprises ephemeris received from one or more GNSS satellites and/or predicted ephemeris. As a source device, the communication device generates, and/or acquires from other resources such as a remote location server, the predicted ephemeris. As a destination device, the communication device receives existing GNSS assistance data from a source device and/or other communication devices in the GNSS group. A GNSS position for the communication device and corresponding time information are used to refresh the received GNSS assistance data. In instances where the communication device further acts as a relay device, the refreshed GNSS assistance data is relayed to other communication devices over wired and/or wireless direct device-to-device connections utilizing appropriate communication technologies such as WiFi, Bluetooth and/or Bluetooth low energy.
摘要:
Aspects of a method and system for timely delivery of multimedia content via a femtocell are provided. In this regard, a femtocell may receive data via an upstream path and transmit data via a downstream path. One of the upstream path and downstream path may comprise a cellular path and the other may comprise a non-cellular path. One or both of the upstream path and the downstream path may be audio video bridging (AVB) paths. Data may be stored in the femtocell based on timing characteristics of one or both of the upstream path and the downstream path. Data may be delivered to the femtocell utilizing best effort delivery and the data may be forwarded by the femtocell with guaranteed quality of service. Resources in the femtocell may be reserved and/or synchronized, utilizing AVB protocols, for communication of one or more data streams.
摘要:
A GNSS enabled mobile device receives GNSS assistance data in a determined format from a central processing station communicatively coupled to a wide area reference network (WARN). The WARN comprises a first plurality of GNSS tracking stations from which usable signals are received by the central processing station, and a second plurality of GNSS tracking stations from which unusable or no signals are received by the central processing station. The central processing station generates the GNSS assistance data using a complete set of GNSS reference feeds of the WARN. The complete set of GNSS reference feeds comprises actual GNSS reference feeds from the first plurality of GNSS tracking stations and virtual GNSS reference feeds derived for the second plurality of GNSS tracking stations from processed actual GNSS reference feeds. The generated GNSS assistance data is reformatted into a determined format and is communicated to the GNSS enabled mobile device, accordingly.
摘要:
A method and apparatus for tracking a signal comprises correlating a digital signal with a code using a hypothesis at a plurality of frequencies and at least one delay to produce correlation results, measuring an energy value of the correlation results, adjusting at least one of the frequency or delay in response to the measured energy value to form the hypothesis.
摘要:
A method and apparatus for processing long term orbit data that is valid for an extended period of time into the future (i.e., long term orbit data). The long term orbit data is processed by reducing redundant information from the data to form compressed long term orbit data.