摘要:
A method for obtaining GNSS time in a GNSS receiver includes: obtaining a time relationship between a first clock signal and the received GNSS time; obtaining a clock value B1 of a second clock signal and further obtaining an associated clock value A1 of the first clock signal to obtain a first pulse relationship at a first time point; calculating a GNSS time C1 corresponding to the clock value A1 according to the time relationship; obtaining a clock value B2 of the second clock signal and further obtaining an associated clock value A2 of the first clock signal to obtain a second pulse relationship at a second time point; and calculating a GNSS time C2 according to the GNSS time C1, the clock value B1, and the clock value B2. Exemplary values of A1, B1, C1, A2 B2, and C2 can be TTick1, FN1, TOW1, TTick2, FN2, and TOW2, respectively.
摘要:
A method for obtaining GNSS time in a GNSS receiver includes: obtaining a time relationship between a first clock signal and the received GNSS time; obtaining a clock value B1 of a second clock signal and further obtaining an associated clock value A1 of the first clock signal to obtain a first pulse relationship at a first time point; calculating a GNSS time C1 corresponding to the clock value A1 according to the time relationship; obtaining a clock value B2 of the second clock signal and further obtaining an associated clock value A2 of the first clock signal to obtain a second pulse relationship at a second time point; and calculating a GNSS time C2 according to the GNSS time C1, the clock value B1, and the clock value B2. Exemplary values of A1, B1, C1, A2 B2, and C2 can be TTick1, FN1, TOW1, TTick2, FN2, and TOW2, respectively.
摘要:
A method and apparatus for obtaining Global navigation Satellite System (GNSS) time in a GNSS receiver are provided. The following steps are included: obtaining a time relationship between a first clock signal and the received GNSS time; obtaining a first clock value of a second clock signal and an first associated clock value of the first clock signal at a first time point; calculating a first GNSS time corresponding to the first clock value of the second clock signal according to the first associated clock value and the time relationship; obtaining a second clock value of the second clock signal and an second associated clock value of the first clock signal at a second time point; and calculating a second GNSS time corresponding to the second associated clock value, according to the first GNSS time, the first clock value and the second clock value of the second clock signal.
摘要:
A method capable of increasing acquisition efficiency in a code division multiple access (CDMA) communication system includes receiving a first signal, generating a second signal by performing a Fourier transform operation for the first signal, determining a plurality of shift signals generated by shifting the second signal a first frequency each time, choosing a pseudo-random code from a plurality of pseudo-random codes and performing a Fourier transform operation for the chosen pseudo-random code, multiplying the plurality of shift signals with a result of performing the Fourier transform operation for the chosen pseudo-random code, and performing an inverse Fourier transform operation for the multiplication result, and determining a status of acquisition.
摘要:
A GNSS satellite signal handling method is disclosed. For a specific Doppler bin, when a peak is found, it is checked if the specific Doppler bin is polluted with interference by detection. If the detection result indicates that the specific Doppler bin is polluted with interference, a threshold, which is used to determine whether the actual signal peak is found or not, is then raised to a higher level, so as to increase the searching reliability. To detect interference, it is determined whether the specific Doppler bin is polluted by comparing a statistical value of correlation results of a plurality of code chip hypotheses with a reference or by checking if there are plural peaks existing in the power spectrum.
摘要:
A receiver capable of enhancing receiving efficiency in a code division multiple access communication system includes a signal reception end for receiving signals, a data output unit for outputting a plurality of data streams corresponding to a plurality of codes according to signals received by the signal reception end, a control unit for outputting a data stream having maximum signal power when an amount of the plurality of data streams is smaller than a first value, a first multiplication unit for multiplying signals received by the signal reception end with the data stream outputted from the control unit, a high pass filter unit for discarding a DC portion of signals outputted from the first multiplication unit, and a second multiplication unit for multiplying the data stream outputted from the control unit with signals outputted from the high pass filtering unit and outputting a multiplied result to the signal reception end.
摘要:
An authorization system of a navigation device includes a first identification (ID) module and a second ID module. The first ID module is arranged to perform authorization for a first portion of the navigation device, and the second ID module is arranged to perform authorization for a second portion of the navigation device. The first and the second ID modules perform bidirectional authorization of the first and the second portions, and further determine behavior of the navigation device according to a result of the bidirectional authorization. An associated authorization method for controlling the navigation device is further provided.
摘要:
An authorization system of a navigation device includes a first identification (ID) module and a second ID module. The first ID module is arranged to perform authorization for a first portion of the navigation device, and the second ID module is arranged to perform authorization for a second portion of the navigation device. The first and the second ID modules perform bidirectional authorization of the first and the second portions, and further determine behavior of the navigation device according to a result of the bidirectional authorization. An associated authorization method for controlling the navigation device is further provided.
摘要:
A method capable of increasing acquisition efficiency in a code division multiple access (CDMA) communication system includes receiving a first signal, generating a second signal by performing a Fourier transform operation for the first signal, determining a plurality of shift signals generated by shifting the second signal a first frequency each time, choosing a pseudo-random code from a plurality of pseudo-random codes and performing a Fourier transform operation for the chosen pseudo-random code, multiplying the plurality of shift signals with a result of performing the Fourier transform operation for the chosen pseudo-random code, and performing an inverse Fourier transform operation for the multiplication result, and determining a status of acquisition.
摘要:
A method and apparatus for obtaining Global navigation Satellite System (GNSS) time in a GNSS receiver are provided. The following steps are included: obtaining a time relationship between a first clock signal and the received GNSS time; obtaining a first clock value of a second clock signal and an first associated clock value of the first clock signal at a first time point; calculating a first GNSS time corresponding to the first clock value of the second clock signal according to the first associated clock value and the time relationship; obtaining a second clock value of the second clock signal and an second associated clock value of the first clock signal at a second time point; and calculating a second GNSS time corresponding to the second associated clock value, according to the first GNSS time, the first clock value and the second clock value of the second clock signal.