A satellite radio-controlled watch, including a receiving unit for receiving a satellite radio wave containing time information and position information; a storage unit for storing intersection point information indicating a position of an intersection point between a reference line along a great circle orthogonal to a specific great circle on the earth or a reference line along the specific great circle on the earth or a circle parallel to the great circle and a time zone boundary, and time difference division information on a wedge-shaped or belt-shaped area that is adjacent to the reference line and to which the intersection point belongs, and a time zone determination unit for determining a time zone, based on the position information, the intersection point information, and the time difference division information.

According to an aspect of the present invention, a device capable of wireless communication includes a counter for counting current time, and a processor for setting a communication mode of the device to one of a notification mode in which the device sends a first notification signal for informing of its existence and a detection mode in which the device detects a second notification signal sent from other device. In the case that the processor changes the communication mode of the device from the notification mode to the detection mode and the second notification signal received in the detection mode includes first time information, the processor corrects time of the counter based on the first time information.

A communication apparatus comprises a communicator that receives a standard time from an external apparatus, a manipulation receiver that receives a time correction action from a user, and a controller that performs a timing processing for clocking time and a time correction processing for correcting the time clocked by the timing processing, on the basis of the standard time received by the communicator, or on the basis of the time correction action received by the manipulation receiver. The controller changes processing contents of the time correction processing until a prescribed time interval has elapsed, when the time clocked by the timing processing is corrected on the basis of the time correction action received by the manipulation receiver.

[Problem] To provide a time synchronization mechanism that is not affected by link asymmetry between time synchronization devices.

[Solution] A DC 4 used in a time transmission system that transmits and receives a PTP packet between a master node 1 and a slave node 2 via the DC 4 and synchronizes time of the slave node 2 based on time information on the transmission and reception includes a PTP clock unit 12 that synchronizes time information by the arrived PTP packet, a frequency clock unit 21 that synchronizes time information by a frequency signal, a delay setting unit 22 that sets, such that a transmission delay of the PTP packet between the master node 1 and the slave node 2 becomes a setting delay Lmax, a waiting time of the PTP packet based on a time difference between a departure time of the PTP packet and an arrival time of the PTP packet at the DC 4, which is determined from the time information of the frequency clock unit 21, and a time adjustment unit 26 that corrects a time shift from reference time in the time information of the frequency clock unit 21 based on the time information of the PTP clock unit 12.

A Reference Time Scale Dissemination System (RTS-DS) is provided that includes a RTS Dissemination Data Provider (RTS-DDP) and a User Terminal. The RTS Dissemination Data Provider is equipped with a radio receiver designed to receive radio signals and to compute a RTS-DDP Computed Time Scale based on received radio signals. The User Terminal (UT) is equipped with a Radio Receiver designed to receive radio signals and to compute a UT Computed Time Scale based on received radio signals, and with a Clock Device designed to be locked to the UT Computed Time Scale and to provide a UT Local Time Scale resultingly locked to the UT Computed Time Scale. The RTS-DPP is designed to receive a Reference Time Scale, and compute, at a RTS-DDP Computed Time, Time Quantities indicative of a difference between the RTS-DDP Computed Time Scale and the received Reference Time Scale, including a Time Scatter indicative of a difference between the RTS-DDP Computed Time and a corresponding Reference Time, and a Time Offset indicative of a mean value, computed over a timespan, of a number of differences between RTS-DDP Computed Times and corresponding Reference Times.

An electronic timepiece includes a storage that stores specific-region DST application rule information and local time information that includes, in association with each other, DST application rules for each region and standard-wave transmitting station information indicating each station transmitting standard waves receivable in the region; a processor that controls clock time to be kept by a clock circuit and displays time to be displayed on a display; and a standard wave receiver that receives standard waves and obtains time information. The processor calibrates the clock time based on the time information indicated by the standard waves received by the standard wave receiver, and controls the display time based on whether the specific-region DST application rule information and the DST application rule information associated with the standard-wave transmitting station information indicating a station transmitting the received standard waves satisfy a predetermined condition.

A sleep training clock can be configured to assist in sleep training. The sleep training clock is shaped like a robot having a face, a torso, and two legs; two LEDs disposed in the face and three LEDs disposed in the torso; and a digital clock face disposed in the torso. Additionally, circuitry for performing sleep training is configured to determine whether the electronic device is in a wake state and turn on the two LEDs disposed in the face and turn off the three LEDs disposed in the torso in response, determine whether the electronic device is in a sleep state and turn off the two LEDs disposed in the face and turn on the three LEDs disposed in the torso in response.

A method for setting an electronic watch including a near-field communication module and a microcontroller configured to exchange electric signals with this module, the method including: establishing a near-field connection between the electronic appliance and the watch; verifying, by way of the microcontroller of the electronic appliance, the accuracy of a datum indicating the clock state of the watch; sending, to the near-field communication module of the watch, by way of the near-field communication device and when instructed to do so by the microcontroller of the electronic appliance, at least one watch setting instruction when the clock state datum is inaccurate; processing said at least one instruction received by means of the microcontroller of the watch, in order to generate watch setting parameters; and configuring the watch when instructed to do so by the microcontroller of the watch, according to the setting parameters generated.

A management apparatus in a time synchronization system includes a time variation information receiving unit configured to acquire time variation information and position information of a time synchronization apparatus, a position information classifying unit configured to classify time synchronization apparatuses into predetermined categories based on the acquired position information, a time variation analysis configured to determine majority based on whether patterns of time variation of the time synchronization apparatuses belonging to an identical category are identical to each other, and to analyze the time variation based on the determined results, and a filtering and delivery unit configured to output an instruction to block the time information received from the positioning satellite, to the time synchronization apparatus having abnormal time variation. A GPS-FW includes a filtering determination unit configured to blocks the time information received from a GPS satellite in a case where a block instruction is received from the management apparatus.

A satellite radiowave receiving device includes a receiver performing a receiving operation of radiowaves transmitted from a positioning satellite and a processor controlling a positioning operation. The processor performs the positioning operation within at least a predetermined maximum positioning interval from a last positioning operation using preliminarily obtained date and time information and valid positional information on the positioning satellite to obtain a current position of the satellite radiowave receiving device and date and time information. The processor causes the receiver to perform the receiving operation within at least a predetermined date and time updating interval shorter than the predetermined maximum positioning interval from a last time when date and time information is obtained from radiowaves transmitted from a positioning satellite to obtain date and time information without the positioning operation.