A radio apparatus is configured to correlate signal data with stored synchronization data to generate synchronization correlation data. The signal data represents a received radio-frequency signal that encodes a data frame having a synchronization preamble comprising a plurality of instances of a predetermined synchronization sequence. The stored synchronization data represents the predetermined synchronization sequence. The synchronization correlation data is generated by correlating signal data representing the synchronization preamble with the stored synchronization data. While generating the synchronization correlation data, the radio apparatus identifies a first set of one or more peaks in the synchronization correlation data, and determines first synchronization information from the first set of one or more peaks. After generating more of the synchronization correlation data, the radio apparatus identifies a second set of one or more peaks in the synchronization correlation data, and determines second synchronization information from the second set of one or more peaks.

A method is provided for acquiring a signal from a satellite in a global navigation satellite system. The signal includes a pseudorandom code. The method includes, for each time period of a plurality of time periods: generating samples of the signal, segments of the samples of the signal are correlated with a local copy of the pseudorandom code, thereby producing correlation values for the time period. A discrete Fourier transform is performed using, as inputs, the correlation values for the respective time period, thereby producing a frequency representation of the correlation values for the time period. The frequency representations of the correlation values for the plurality of time periods are combined according to a data hypothesis. When a magnitude of the combined frequency representations meets predefined criteria, a frequency corresponding to the magnitude is selected as a tracking frequency for the satellite.

A method and system are provided. The method includes receiving, by a GNSS receiver, a GNSS signal, rotating, by a carrier rotator, samples of the GNSS signal with carrier phase inputs, inverting, by a chip matched filter (CMF), the rotated samples, and generating, by the CMF, an output based on the inverted samples.

A method and system are provided. The method includes receiving, by a GNSS receiver, a GNSS signal, rotating, by a carrier rotator, samples of the GNSS signal with carrier phase inputs, inverting, by a chip matched filter (CMF), the rotated samples, and generating, by the CMF, an output based on the inverted samples.

A personal navigation device includes a correlator for processing GNSS signals from a constellation of satellites A signal is received from a navigation beacon containing a repeating code word, in which the code word includes a number N of samples corresponding to N phases, and in which reception of each code word occurs within a defined time period T. The sequence of N code samples is correlated with a known code word to determine a maximum value of correlation for a particular phase of the received signal. The correlation is performed using a correlator of size M, in which M is less than N, such that N/M=P complete correlations for a partial code phase are performed such that each correlation of a partial code phase is performed within a time period of approximately T/P. All P correlations of partial code phases are completed within time T.

A multi-radio border router for synchronizing communications of multiple border router radios is provided. For example, the border router includes a border router component connected to each of the plurality of border router radios. The border router component configured for selecting one of the plurality of border router radios as a master radio and assigning channel offset parameters for each of the plurality of border router radios. The master radio is configured for broadcasting synchronization beacons based on which the non-master radios synchronize their respective clocks with that of the master radio. After the synchronization, each of the border router radios communicates with endpoints associated therewith according to a channel hopping pattern modified by applying a channel offset determined based on the channel offset parameters assigned to the respective radio.

The invention concerns a method of resolving a time ambiguity in a receiver based on a received radio signal. The radio signal comprises a first signal component and a second signal component. The first signal component comprises a first code of X.sub.1 code symbols, the first code having a duration of C.sub.1 units of time, wherein each of the code symbols has a duration of St units of time. Likewise, the second signal component comprises a second code of X.sub.2 code symbols, the second code having a duration of C2 units of time, wherein each of the code symbols has a duration of S.sub.2 units of time. Either, the code duration C.sub.1 of the first signal component and the code duration C.sub.2 of the second signal component are chosen such that the start or the end of the first code and the second code have a reference code phase offset of D units of time every 2 N units of time, wherein 2N is equivalent to the least common multiple of C.sub.1 and C.sub.2. Or, the code duration C.sub.1 of the first signal component and the code symbol duration S.sub.2 of the second signal component are chosen such that the start or the end of the first code and the second code symbol have a reference code phase offset of D units of time every 2N units of time, wherein 2N is equivalent to the least common multiple of C.sub.1 and S.sub.2. The method comprises acquiring each of the first and second signal components, and performing code symbol synchronization and/or code synchronization for each of the first code and the second code. The method further comprises estimating a code phase offset between the synchronized first code and the synchronized second code, or a code-symbol phase offset between the synchronized first code and the synchronized second code symbol. Finally, the method comprises resolving the time ambiguity of the receiver within a ±N units of time period based on the time-dependent code phase offset or the time-dependent code-symbol phase offset. The invention further concerns radio signal devices.

The invention concerns a method of resolving a time ambiguity in a receiver based on a received radio signal. The radio signal comprises a first signal component and a second signal component. The first signal component comprises a first code of X.sub.1 code symbols, the first code having a duration of C.sub.1 units of time, wherein each of the code symbols has a duration of St units of time. Likewise, the second signal component comprises a second code of X.sub.2 code symbols, the second code having a duration of C2 units of time, wherein each of the code symbols has a duration of S.sub.2 units of time. Either, the code duration C.sub.1 of the first signal component and the code duration C.sub.2 of the second signal component are chosen such that the start or the end of the first code and the second code have a reference code phase offset of D units of time every 2 N units of time, wherein 2N is equivalent to the least common multiple of C.sub.1 and C.sub.2. Or, the code duration C.sub.1 of the first signal component and the code symbol duration S.sub.2 of the second signal component are chosen such that the start or the end of the first code and the second code symbol have a reference code phase offset of D units of time every 2N units of time, wherein 2N is equivalent to the least common multiple of C.sub.1 and S.sub.2. The method comprises acquiring each of the first and second signal components, and performing code symbol synchronization and/or code synchronization for each of the first code and the second code. The method further comprises estimating a code phase offset between the synchronized first code and the synchronized second code, or a code-symbol phase offset between the synchronized first code and the synchronized second code symbol. Finally, the method comprises resolving the time ambiguity of the receiver within a ±N units of time period based on the time-dependent code phase offset or the time-dependent code-symbol phase offset. The invention further concerns radio signal devices.

A method is provided for acquiring a signal from a satellite in a global navigation satellite system. The signal includes a pseudorandom code. The method includes, for each time period of a plurality of time periods: generating samples of the signal, segments of the samples of the signal are correlated with a local copy of the pseudorandom code, thereby producing correlation values for the time period. A discrete Fourier transform is performed using, as inputs, the correlation values for the respective time period, thereby producing a frequency representation of the correlation values for the time period. The frequency representations of the correlation values for the plurality of time periods are combined according to a data hypothesis. When a magnitude of the combined frequency representations meets predefined criteria, a frequency corresponding to the magnitude is selected as a tracking frequency for the satellite.

The present disclosure describes a method and an apparatus for pruning false peaks during slot synchronization at a user equipment (UE). For example, a method is provided to identify a plurality of first peaks associated with a primary-synchronization channel (P-SCH) received at the UE and a plurality of second peaks from the plurality of first peaks. Further, one or more pruning locations along with associated energy thresholds for each of the plurality of the second peaks may be determined and whether a peak of the plurality of the first peaks is a false peak is identified based on whether the peak is located at one of the one or more pruning locations of the peak and an associated energy value of the peak does not satisfy the associated energy threshold of the pruning location. Furthermore, the peak identified as the false peak is discarded.