An electronic watch includes a GPS receiver, a first time correction unit configured to correct time using the time information received by the GPS receiver, a beacon receiver configured to receive a beacon signal containing beacon identification information transmitted from a beacon installed indoors, a first storage unit configured to store beacon identification information and time difference information corresponding to the beacon identification information, a second time correction unit configured to correct a time difference using the beacon signal received by the beacon receiver and the time difference information stored in the first storage unit, and a button configured to accept a reception instruction of the beacon signal, which is operated by an operator. The beacon receiver is configured to receive a beacon signal when the button accepts the reception instruction.

An electronic watch includes a GPS receiver, a first time correction unit configured to correct time using the time information received by the GPS receiver, a beacon receiver configured to receive a beacon signal containing beacon identification information transmitted from a beacon installed indoors, a first storage unit configured to store beacon identification information and time difference information corresponding to the beacon identification information, a second time correction unit configured to correct a time difference using the beacon signal received by the beacon receiver and the time difference information stored in the first storage unit, and a button configured to accept a reception instruction of the beacon signal, which is operated by an operator. The beacon receiver is configured to receive a beacon signal when the button accepts the reception instruction.

Systems and methods of storing phase history, and enhancing and restoring phase accuracy for a embedded Global Navigation Satellite System (GNSS) receiver include storing a phase history of the GNSS receiver output; determining an expected value of phase of the GNSS receiver output based on the phase history; and, responsive to a degradation of the GNSS receiver output, adjusting the GNSS receiver output utilizing the expected value of phase. The systems and method can further include, responsive to degradation being a loss of the GNSS receiver output, utilizing a holdover output from a physical frequency reference and with a phase adjusted based on the expected value of phase, and, responsive to the variation, utilizing the phase history to re-generate the GNSS receiver output for performance enhancement.

Systems and methods of storing phase history, and enhancing and restoring phase accuracy for a embedded Global Navigation Satellite System (GNSS) receiver include storing a phase history of the GNSS receiver output; determining an expected value of phase of the GNSS receiver output based on the phase history; and, responsive to a degradation of the GNSS receiver output, adjusting the GNSS receiver output utilizing the expected value of phase. The systems and method can further include, responsive to degradation being a loss of the GNSS receiver output, utilizing a holdover output from a physical frequency reference and with a phase adjusted based on the expected value of phase, and, responsive to the variation, utilizing the phase history to re-generate the GNSS receiver output for performance enhancement.

Systems and methods of storing phase history, and enhancing and restoring phase accuracy for a embedded Global Navigation Satellite System (GNSS) receiver include storing a phase history of the GNSS receiver output; determining an expected value of phase of the GNSS receiver output based on the phase history; and, responsive to a degradation of the GNSS receiver output, adjusting the GNSS receiver output utilizing the expected value of phase. The systems and method can further include, responsive to degradation being a loss of the GNSS receiver output, utilizing a holdover output from a physical frequency reference and with a phase adjusted based on the expected value of phase, and, responsive to the variation, utilizing the phase history to re-generate the GNSS receiver output for performance enhancement.

An electronic watch includes a GPS receiver, a first time correction unit configured to correct time using the time information received by the GPS receiver, a beacon receiver configured to receive a beacon signal containing beacon identification information transmitted from a beacon installed indoors, a first storage unit configured to store beacon identification information and time difference information corresponding to the beacon identification information, a second time correction unit configured to correct a time difference using the beacon signal received by the beacon receiver and the time difference information stored in the first storage unit, and a button configured to accept a reception instruction of the beacon signal, which is operated by an operator. The beacon receiver is configured to receive a beacon signal when the button accepts the reception instruction.

A timing signal generation device includes a GPS receiver, an atomic oscillator, a phase comparator, a loop filter, and a divider, a temperature sensor, a DDS, and a DSP. The GPS receiver outputs a reference timing signal. The atomic oscillator outputs a clock signal in accordance with an input voltage value. The phase comparator, the loop filter, and the divider adjust the voltage value in accordance with a synchronization status between the reference timing signal and the clock signal. The temperature sensor outputs a signal depending on the temperature of the atomic oscillator. The DDS converts the frequency of the clock signal and outputs a signal obtained by converting the frequency. The DSP controls the DDS based on an output of the temperature sensor.

A timing signal generating device includes a GPS receiver and a processing unit. The GPS receiver functions as a positioning calculation unit, and receives satellite signals transmitted from GPS satellites and performs positioning calculation based on trajectory information and time information contained in the received satellite signals. Further, the processing unit functions as a position information generation unit, and generates position information of a receiving point based on a mode value or a median value in results of the positioning calculation at a plurality of times by the GPS receiver.

A timing signal generating device includes a GPS receiver and a processing unit. The GPS receiver functions as a positioning calculation unit, and receives satellite signals transmitted from GPS satellites and performs positioning calculation based on trajectory information and time information contained in the received satellite signals. Further, the processing unit functions as a position information generation unit, and generates position information of a receiving point based on a mode value or a median value in results of the positioning calculation at a plurality of times by the GPS receiver.

A timing signal generation device includes a GPS receiver, an atomic oscillator, a phase comparator, a loop filter, and a divider, a temperature sensor, a DDS, and a DSP. The GPS receiver outputs a reference timing signal. The atomic oscillator outputs a clock signal in accordance with an input voltage value. The phase comparator, the loop filter, and the divider adjust the voltage value in accordance with a synchronization status between the reference timing signal and the clock signal. The temperature sensor outputs a signal depending on the temperature of the atomic oscillator. The DDS converts the frequency of the clock signal and outputs a signal obtained by converting the frequency. The DSP controls the DDS based on an output of the temperature sensor.