CIRCUIT FOR DETECTING THE PHASE OF RECEIVED SIGNAL

摘要

A small-scale circuit for detecting the phase of a received signal. The circuit functions so as to capture a frame synchronizing signal from a demodulated baseband signal, extract a symbol stream during the period of frame synchronizing signal from the demodulated baseband signal through delay circuits (41, 42) at a timing matching the bit stream of the captured synchronizing signal, rotating the phase of a corresponding symbol extracted from the symbol stream when the bit in the bit stream is logic "0" by 180 DEG , outputting the symbol after the phase rotation and a corresponding symbol extracted from the symbol stream when the bit in the bit stream is logic "1" from a 0 DEG /180 DEG phase rotating circuit (43), operating the cumulative average of the output from the 0 DEG /180 DEG phase rotating circuit (43) for a specific period through cumulative averaging circuits (45, 46), rotating the phases of the outputs therefrom through a 22.5 DEG phase rotating circuit (48), and determining the phase of the output therefrom by a phase determining circuit (49).