A satellite-synchronized network clock may include an oscillator, a global navigation satellite system (GNSS) time receiver module, and a control subsystem. The GNSS time receiver module may include a time receiver, a multiplexer, and a plurality of source inputs. The control subsystem may configure the multiplexer and time receiver of the GNSS time receiver module to sequentially receive time signals from a plurality of GNSS satellite constellations. Methods of synchronizing multiple time sources may include sequentially receiving a first time signal from a first GNSS constellation, a second time signal from a second GNSS constellation, and a third time signal from a third GNSS constellation with a GNSS receiver. The methods may further include measuring a phase and frequency offset of each respective received time signal relative to an oscillator and comparing the measured offsets to determine the accuracy of each of the received time signals.

A processor of a satellite radio wave receiving device processes radio waves received by a receiver to identify a bit value in each of divided unit time segments that are obtained by dividing a time period of one bit into a plurality of unit time segments of equal duration; creates a bit array having the identified bit values in respective divided unit time segments by sequentially arranging the identified bit values in an order of receipt, the one or more processors creating said bit array in a plurality by successively shifting a time at which the bit array starts by one unit time segment; and performs a bit edge detection operation by detecting a head timing of the bit data at which a bit value changes in the received radio waves based on said plurality of bit value arrays.

A processor of a satellite radio wave receiving device processes radio waves received by a receiver to identify a bit value in each of divided unit time segments that are obtained by dividing a time period of one bit into a plurality of unit time segments of equal duration; creates a bit array having the identified bit values in respective divided unit time segments by sequentially arranging the identified bit values in an order of receipt, the one or more processors creating said bit array in a plurality by successively shifting a time at which the bit array starts by one unit time segment; and performs a bit edge detection operation by detecting a head timing of the bit data at which a bit value changes in the received radio waves based on said plurality of bit value arrays.

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.

A device having: one or more processors for determining an elapsed time since a correction of a calculated date and time; estimate a degree of deviation included in the calculated date and time, based on the elapsed time; and in response to estimating the degree of deviation to be equal to or smaller than a predetermined range, execute a method by which the one or more processors: generate an expected code sequence of a code sequence to be received from a satellite; control a satellite radio wave receiver to receive the code sequence; determine whether there is a match between the expected code sequence and the code sequence; in response to determining that there is a match, obtain a present date and time information represented by the expected code sequence; and correct the calculated date and time, based on the present date and time information obtained.

A device having: one or more processors for determining an elapsed time since a correction of a calculated date and time; estimate a degree of deviation included in the calculated date and time, based on the elapsed time; and in response to estimating the degree of deviation to be equal to or smaller than a predetermined range, execute a method by which the one or more processors: generate an expected code sequence of a code sequence to be received from a satellite; control a satellite radio wave receiver to receive the code sequence; determine whether there is a match between the expected code sequence and the code sequence; in response to determining that there is a match, obtain a present date and time information represented by the expected code sequence; and correct the calculated date and time, based on the present date and time information obtained.

An electronic device has a GPS receiver that receives satellite signals transmitted from positioning information satellites and computes positioning information; a first storage unit that stores the positioning information and local time information including local time computing information related to the time in the region identified by the positioning information; an update information receiving unit that receives update information for the local time information from an update information transmission device; a second storage unit that stores the update information; a local time computing information acquisition unit that acquires the local time computing information from the first storage unit when the local time computing information corresponding to the positioning information is stored only in the first storage unit, and acquires the local time computing information from the second storage unit when the local time computing information is stored in the second storage unit.

An electronic device has a GPS receiver that receives satellite signals transmitted from positioning information satellites and computes positioning information; a first storage unit that stores the positioning information and local time information including local time computing information related to the time in the region identified by the positioning information; an update information receiving unit that receives update information for the local time information from an update information transmission device; a second storage unit that stores the update information; a local time computing information acquisition unit that acquires the local time computing information from the first storage unit when the local time computing information corresponding to the positioning information is stored only in the first storage unit, and acquires the local time computing information from the second storage unit when the local time computing information is stored in the second storage unit.

An electronic device includes: a receiver that receives a satellite signal; and a time corrector that corrects an internal time. The receiver acquires time synchronization information and satellite time information by receiving the satellite signal, detects update timing of seconds on the basis of the time synchronization information, and executes output processing of outputting a synchronization signal, which indicates output timing, and reception side time information including time difference information, which indicates a time difference between the update timing of seconds and the output timing, and time information of hours, minutes, and seconds based on the satellite time information, before next update timing of seconds. The time corrector corrects the internal time on the basis of the synchronization signal and the reception side time information.