Abstract: A wireless communication system having a time synchronization mechanism is provided. The wireless communication system comprises a first receiver and a second receiver. The first receiver tracks a code phase data of a satellite to generate a synchronization data related to a sync phase position and a first receiver phase position corresponding to one of first receiver time pulses. The second receiver comprises a receiving unit, a tracking unit and a computing unit. The receiving unit receives the synchronization data from the first receiver through a network. The tracking unit tracks the code phase data of the satellite to obtain a second receiver phase position corresponding to one of second receiver time pulses. The computing unit performs a time synchronization process with the first receiver and the satellite according to the code phase data, the synchronization data and the second receiver phase position.

Abstract: A wireless communication system having a time synchronization mechanism is provided. The wireless communication system comprises a first receiver and a second receiver. The first receiver tracks a code phase data of a satellite to generate a synchronization data related to a sync phase position and a first receiver phase position corresponding to one of first receiver time pulses. The second receiver comprises a receiving unit, a tracking unit and a computing unit. The receiving unit receives the synchronization data from the first receiver through a network. The tracking unit tracks the code phase data of the satellite to obtain a second receiver phase position corresponding to one of second receiver time pulses. The computing unit performs a time synchronization process with the first receiver and the satellite according to the code phase data, the synchronization data and the second receiver phase position.

Abstract: In an apparatus of correcting a clock drift error, a receiver unit receives a first GNSS signal from a satellite. A Doppler correction unit obtains a first predicted frequency. A tracking unit can obtain a first tracked frequency. The satellite-positioning unit determines a clock offset based on a position fix. A computation unit calculates a first difference between the first predicted and tracked frequencies. When the receiver unit is turned off and then on for receiving a second GNSS signal from the satellite, the Doppler correction unit obtains a second predicted frequency, the tracking unit obtains a second tracked frequency, and the computation unit calculates a second difference between the second predicted and tracked frequencies. An error correction unit computes an estimated clock offset according to the clock offset, the first difference, and the second difference.

Abstract: In an apparatus of correcting a clock drift error, a receiver unit receives a first GNSS signal from a satellite. A Doppler correction unit obtains a first predicted frequency. A tracking unit can obtain a first tracked frequency. The satellite-positioning unit determines a clock offset based on a position fix. A computation unit calculates a first difference between the first predicted and tracked frequencies. When the receiver unit is turned off and then on for receiving a second GNSS signal from the satellite, the Doppler correction unit obtains a second predicted frequency, the tracking unit obtains a second tracked frequency, and the computation unit calculates a second difference between the second predicted and tracked frequencies. An error correction unit computes an estimated clock offset according to the clock offset, the first difference, and the second difference.

Abstract: An apparatus and a method for collecting navigation data are disclosed, where the apparatus includes a correlator, a first buffer, a first calculating unit and a management unit. The correlator can generate a plurality of power bits based on navigation data of a satellite. The first buffer can store a sequence of power bits from the correlator before bit synchronization is completed. The first calculating unit can generate at least one first data bit of a subframe based on the sequence of power bits. The management unit can integrate the at least one first data bit with other data bits of the subframe, so as to constitute the subframe completely.