Patent ID: 6067332
Filing Date: 2000-05-23
Classification: H03J,H04H

Abstract:
A method of automatically searching for a receivable digital audio broadcast signal having a bandwidth substantially equal to a certain quantity f.sub.1, the receivable digital audio broadcast signal being divided into frames, each frame having a frame synchronization symbol, comprising the steps of:(a) setting a digital audio broadcast receiver to a certain receiving frequency;(b) detecting a resulting level of a received signal;(c) changing said receiving frequency by an amount at least equal to said quantity f.sub.1, and returning to said step (b), if the level of said received signal is below a predetermined threshold;(d) attempting to detect said frame synchronization symbol in said received signal, if the level of said received signal is above said threshold;(e) changing said receiving frequency by an amount at least equal to said quantity f.sub.1, and returning to said step (b), if said frame synchronization symbol cannot be detected;(f) attempting to find a center frequency of said digital audio broadcast signal by demodulating said received signal, after said frame synchronization symbol has been detected;(g) changing said receiving frequency by an amount at least equal to said quantity f.sub.1, and returning to said step (b), if said center frequency cannot be found; and(h) setting said receiving frequency to said center frequency, when said center frequency has been found.