A satellite radio wave receiving device includes: a receiver that receives a satellite radio wave to identify a reception signal; and a processor that acquires primary date and time information from the identified reception signal and outputs a date and time notifying signal indicating date and time based on the primary date and time information to an outside of the satellite radio wave receiving device. The date and time notifying signal includes at least a timing notifying signal indicating a predetermined timing. The processor determines the predetermined timing without consideration of a timing of a second synchronization point which is a leading edge of every second in the date and time based on the primary date and time information, and outputs the timing notifying signal at the predetermined timing.

A satellite radio wave receiving device includes: a receiver that receives a satellite radio wave to identify a reception signal; and a processor that acquires primary date and time information from the identified reception signal and outputs a date and time notifying signal indicating date and time based on the primary date and time information to an outside of the satellite radio wave receiving device. The date and time notifying signal includes at least a timing notifying signal indicating a predetermined timing. The processor determines the predetermined timing without consideration of a timing of a second synchronization point which is a leading edge of every second in the date and time based on the primary date and time information, and outputs the timing notifying signal at the predetermined timing.

A radio-controlled timepiece, including: a radio wave reception unit that receives satellite waves and extracts an incoming code sequence formatted in a prescribed format from the received satellite waves; and a processor that generates in advance an expected code sequence that is expected to be part of the incoming code sequence and detects a matching code sequence segment, within the incoming code sequence, that has a degree of match with the expected code sequence that satisfies a prescribed matching condition, the processor determining a present date/time, as indicated by the satellite waves, in accordance with a timing at which the detected matching code sequence segment occurs within the incoming code sequence as measured by time kept by the timepiece.

A radio-controlled timepiece, including: a radio wave reception unit that receives satellite waves and extracts an incoming code sequence formatted in a prescribed format from the received satellite waves; and a processor that generates in advance an expected code sequence that is expected to be part of the incoming code sequence and detects a matching code sequence segment, within the incoming code sequence, that has a degree of match with the expected code sequence that satisfies a prescribed matching condition, the processor determining a present date/time, as indicated by the satellite waves, in accordance with a timing at which the detected matching code sequence segment occurs within the incoming code sequence as measured by time kept by the timepiece.

A communication system (1) comprises a central (100) and a peripheral (200). The central (100) receives location information and time information from NTP servers (10) and a location server (30). The central (100) creates first offset information of the time measured by its own device and the time information received from the NTP servers (10). The central (100) acquires from map information a time difference corresponding to a location presented by the location information received from the location server (30). The central (100) creates first updated time information based on the time measured by its own device, first offset information, and time difference corresponding to the location presented by the location information received from location server (30) and transmits the first updated time information to the peripheral (200). The peripheral (200) changes the time displayed by its own device based on the received first updated time information.

A communication system (1) comprises a central (100) and a peripheral (200). The central (100) receives location information and time information from NTP servers (10) and a location server (30). The central (100) creates first offset information of the time measured by its own device and the time information received from the NTP servers (10). The central (100) acquires from map information a time difference corresponding to a location presented by the location information received from the location server (30). The central (100) creates first updated time information based on the time measured by its own device, first offset information, and time difference corresponding to the location presented by the location information received from location server (30) and transmits the first updated time information to the peripheral (200). The peripheral (200) changes the time displayed by its own device based on the received first updated time information.

The present application at least describes a method for predictive clock modeling. The method may include a step of collecting a characteristic of a first clock disposed therein via a first node. The method may also include a step of collecting a characteristic of a second clock disposed therein via a second node. The method may also include a step of receiving an instance of time of the first clock via the first node. The method may further include a step of receiving an instance of time of the second clock via the second node. The method may even further include a step of causing to determine a time offset and/or frequency offset between the first and second clock via a model based on the collected characteristic and the received instance of time from each of the first and second nodes. The method may yet even further include a step of transmitting an indication of the determined time offset and/or frequency offset output from the model to the second node.

The present application at least describes a method for predictive clock modeling. The method may include a step of collecting a characteristic of a first clock disposed therein via a first node. The method may also include a step of collecting a characteristic of a second clock disposed therein via a second node. The method may also include a step of receiving an instance of time of the first clock via the first node. The method may further include a step of receiving an instance of time of the second clock via the second node. The method may even further include a step of causing to determine a time offset and/or frequency offset between the first and second clock via a model based on the collected characteristic and the received instance of time from each of the first and second nodes. The method may yet even further include a step of transmitting an indication of the determined time offset and/or frequency offset output from the model to the second node.

A time synchronization method that is capable of selecting whether synchronization, by a timepiece unit that generates a time signal synchronized with a standard time and outputs it to an exterior, with the time is performed by time information obtained by receiving a radio wave including information relating to the time, or is performed by means of a holdover performed using a clock signal from an internal or external clock source. A schedule having a first time period in which the above-mentioned time information is used, and a second time period by means of the holdover is determined according to temporal reception characteristics of the radio wave at a reception location of the radio wave, and according to the schedule, supplying the timepiece unit with the time information or supplying the timepiece unit with the clock signal from the internal or external clock source.

A time synchronization method that is capable of selecting whether synchronization, by a timepiece unit that generates a time signal synchronized with a standard time and outputs it to an exterior, with the time is performed by time information obtained by receiving a radio wave including information relating to the time, or is performed by means of a holdover performed using a clock signal from an internal or external clock source. A schedule having a first time period in which the above-mentioned time information is used, and a second time period by means of the holdover is determined according to temporal reception characteristics of the radio wave at a reception location of the radio wave, and according to the schedule, supplying the timepiece unit with the time information or supplying the timepiece unit with the clock signal from the internal or external clock source.