DIGITAL CLOCK USING CDMA SIGNAL

摘要

PURPOSE: A digital clock using a CDMA signal is provided to obtain the accurate time information by extracting time information from a received CDMA signal. CONSTITUTION: A digital clock using a CDMA signal includes a CDMA receiver(10), a system clock(30), a synchronization part(20), and a time indication part(40). The CDMA receiver(10) extracts the time information and a reference clock from a received CDMA signal. The system clock(30) generates a system clock according to a control signal. The synchronization part(20) receives the reference clock and the system clock, detects a phase difference, generates the control signal according to the detected phase difference signal, and outputs a timing signal by filtering the phase difference signal. The time indication part(40) receives a time information signal and a timing signal and synchronizes the time information signal with the timing signal. The synchronization part includes a phase detector for detecting a phase difference between the reference clock and the system clock and a filter for generating the control signal according to the phase difference signal and outputting a timing information signal by filtering the phase difference signal. The system clock includes a D/A converter for converting the control signal to an analog signal and a voltage controlled generator for generating the system clock.