FRAME SYNCHRONIZATION SYSTEM AND ITS CIRCUIT

摘要

PROBLEM TO BE SOLVED: To acquire a frame synchronization position more stably even when a level fluctuation takes place by excluding the effect of jitter due to a noise at a receiver side caused when frame synchronization is taken with a simple configuration. SOLUTION: A correlation section 11 obtains a correlation signal (a) between a time division multiplex digital radio transmission signal to which a synchronizing signal is inserted and a predetermined synchronization pattern. A level comparison section 12 compares the correlation signal (a) with preset threshold value VTH and provides an output of a pulse (b) having a width of a time Δt in excess of the threshold value. A width calculation section 13 obtains the time Δt equivalent to the pulse width of the pulse (b) and calculates the half Δt/2 of the time Δt. The pulse (b) outputted from the level comparison section 12 is delayed by the half Δt/2 of the time Δt at a delay section 14 to provide a frame synchronization timing signal (c) rising almost at a peak of the correlation peak waveform.