US Patent 7551521 Time information receiver and radio controlled watch

A time information receiver and radio controlled watch that receives a time code in which different data pulses are disposed one in a unit period. A composite signal waveform of a plurality of detected signals of the time code shifted sequentially by a unit period of 1 second is obtained by sample adders. A start point of each unit period is detected from the composite signal waveform as a seconds synchronization point where the receiver and watch is seconds-synchronized with the time code. An accurate seconds synchronization point is detected from the detected signal even when the same includes a considerable noise.