A three-frequency cycle slip detection method of a BDS based on Doppler integration assistance includes: performing an epoch integration on three-frequency Doppler observation values to obtain a three-frequency Doppler integration value, determining an epoch pseudo-range variable according to the three-frequency Doppler integration value, determining the epoch carrier phase variable according to the frequency carrier phase observation values, determining two groups of optimal three-frequency carrier phase combination coefficients according to the combination observation wavelength, the ionospheric delay coefficient, and the root mean square error of the pseudo-range phase combination cycle slip detection variable, determining a three-frequency STPIR slip detection variable and a three-frequency STPIR cycle slip detection threshold, and constructing three-frequency cycle slip solution equations according to the two groups of optimal three-frequency carrier phase combination coefficients, and obtaining a cycle slip value at a single frequency by solving the three-frequency cycle slip solution equations.

A method, electronic device, and system are herein disclosed. The method includes loading a plurality of available satellite signal carriers, generating a hypothesis for each of the plurality of available satellite signal carriers, combining the plurality of available satellite signal carriers into a number of signal combinations based on the created hypotheses, and determining whether a satellite signal is detected with one of the number of signal combinations.

A method of processing a satellite signal includes: receiving a satellite positioning system (SPS) signal, including an SPS data signal of unknown data content, from a satellite at a wireless communication device; receiving symbol indications, of determined symbol values, from a terrestrial wireless communication system at the wireless communication device; correlating the SPS data signal with a pseudo-random noise code to obtain first correlation results; and using the symbol indications and the first correlation results to determine a measurement of the SPS signal.

Aspects of the disclosure provide an apparatus that includes a receiving circuit and a processing circuit. The receiving circuit is configured to receive a satellite signal transmitted from a satellite. The satellite signal carries navigation bits that are transmitted with a navigation bit length. The processing circuit is configured to construct aiding navigation bits based on aiding ephemeris and almanac information that are provided by an aiding source other than the satellite signal. Further, the processing circuit is configured to strip the navigation bits from the satellite signal based on the aiding navigation bits to generate a post-stripping signal, and perform an integration on the post-stripping signal.

Methods and systems for cross-protocol time synchronization may comprise, for example, in a premises-based network, receiving a signal that conforms to a data over cable service interface specification (DOCSIS) communications protocol. A global time of day (GTOD) clock may be extracted from the received signal. Communication on the premises-based network in accordance with a multimedia over cable alliance (MoCA) communications protocol may be synchronized based at least in part on the extracted GTOD clock. Communication in a third communications protocol may be synchronized, wherein the third communications protocol may include a home phoneline networking alliance (HPNA) standard, an IEEE 802.11x standard, and a non-public wireless network protocol. The extracted GTOD clock may comprise a GPS clock, GLONASS clock, and a Galileo clock. A second signal for extracting a GTOD may be received, such as a satellite signal, and may conform to a low Earth orbit satellite signal protocol.

Certain implementations of the disclosed technology may include systems and methods for reducing noise in dual-frequency GNSS signal observation. The method can include: receiving, at a GNSS receiver, a first signal and a second signal. At least the second signal includes noise. The first signal is characterized by a first carrier frequency, and the second signal is characterized by a second carrier frequency. The method includes: down converting, sampling, cross-correlating, accumulating, determining ambiguous instantaneous phases, determining non-ambiguous instantaneous phases, producing normalized non-ambiguous instantaneous first phase samples, constructing a normalized first counter rotation phasor, generating a counter-rotated second observable, applying a low pass filter to remove noise; and outputting the filtered second observable.

A signal acquiring unit (3) performs signal detection and initial synchronization on an output from a RF frontend (2) by performing circular convolution operation using a first code replica corresponding to a case where a ranging code does not change in polarity and a second code replica corresponding to a case where a ranging code changes in polarity. A signal tracking unit (4) performs synchronization tracking using a result of signal acquisition output from the signal acquiring unit (3) as an initial value.

Methods and systems for cross-protocol time synchronization may comprise, for example, in a premises-based network, receiving a signal that conforms to a data over cable service interface specification (DOCSIS) communications protocol. A global time of day (GTOD) clock may be extracted from the received signal. Communication on the premises-based network in accordance with a multimedia over cable alliance (MoCA) communications protocol may be synchronized based at least in part on the extracted GTOD clock. Communication in a third communications protocol may be synchronized, wherein the third communications protocol may include a home phoneline networking alliance (HPNA) standard, an IEEE 802.11x standard, and a non-public wireless network protocol. The extracted GTOD clock may comprise a GPS clock, GLONASS clock, and a Galileo clock. A second signal for extracting a GTOD may be received, such as a satellite signal, and may conform to a low Earth orbit satellite signal protocol.

The carrier phase ready coherent acquisition of a global navigation satellite system (GNSS) snapshot signal includes receiving in a snapshot receiver different GNSS signals from correspondingly different GNSS satellites, and performing multi-hypothesis (MH) acquisition upon each of GNSS signal in order to produce a complete set of secondary code index hypotheses, each hypothesis producing a corresponding acquisition result according to an identified peak at a correct code-phase and Doppler frequency. The secondary code index hypotheses are adjusted for each different GNSS signal based upon a flight time difference determined for each GNSS satellite, so as to produce a new set of hypotheses. Finally, one of the hypotheses in the new set may be selected as a correct hypothesis according to a predominate common index amongst the hypotheses in the new set, and the acquisition results for each of the different GNSS signals may be filtered utilizing the correct hypothesis.

A GNSS receiver to track low power GNSS satellite signals. The GNSS receiver includes a frequency locked loop (FLL) that measures a current doppler frequency of the satellite signal. A delay locked loop (DLL) measures a current code phase delay of the satellite signal. A current operating point corresponds to the current doppler frequency and the current code phase delay of the satellite signal. A grid monitor receives the satellite signal and the current operating point, and measures a satellite signal strength at a plurality of predefined offset points from the current operating point. The FLL and the DLL are centered at the current operating point. A peak detector is coupled to the grid monitor and processes the satellite signal strengths at the plurality of predefined offset points and re-centers the FLL and the DLL to a predefined offset point with the satellite signal strength above a predefined threshold.