| 摘要 |
<p>PROBLEM TO BE SOLVED: To shorten the time for initial synchronization acquisition in a spread spectrum signal receiver of an FH(frequency hopping) system. SOLUTION: In the initial synchronization acquisition, the frequency signals of this receiver are fixed and a hopping frequency is turned to a single state. When transmission signals to be frequency hopped and transmitted become a prescribed frequency, the IF signals of,Δf equal to or more than a reference voltage are generated and output signals are generated from a comparator circuit 6. Also, when desired ID signals are detected from the output of a demodulation circuit 4, detection signals are generated from a CPU 7. Then, control signals are generated from a control circuit 8, a PN code generation circuit 9 is operated and frequency hopping synchronized with a transmission side is started.</p> |
