Timing and Time Information Extraction from a Phase Modulated Signal in a Radio Controlled Clock Receiver

摘要

A system and method for a radio controlled clock receiver adapted to extract timing and time information from a phase modulated signal. The official time signal is broadcast from a central location using the modified modulation scheme of the present invention, which adds phase modulation that allows for greatly improved performance. The information modulated onto the phase contains a known synchronization sequence having good autocorrelation properties, error-correcting coding for the time information and notifications of daylight-saving-time (DST) transitions that are provided months in advance. The modulation scheme is based on a form of phase modulation, such as binary-phase-shift-keying (BPSK) or phase reversal keying (PRK). A superframe comprising multiple frames with repeated information allows for the accumulation of received energy over multiple frames to provide for a corresponding gain in the receiver.