| 摘要 |
PURPOSE:To avoid waveform distortion at pull-in by inverting a detected waveform to generate a synchronizing pulse at a point where the area of an asynchronous part is divided equally into two in a synchronizing device in synchronizing with a frequency changing point of the FSK frequency hopping communication system. CONSTITUTION:A frequency hopping receiving signal is converted into an intermediate frequency by an output of a local oscillator 2 and a mixer 3 and inputted to an envelope detector 5 via a filter 4 for eliminating unnecessary signal. Then, OV and EV of this signal are inverted by a level shift inverting circuit 7 and inputted to an integration circuit 7 performing positive and negative integration by H,L level of an output of an internal hopping synchronizing signal generating circuit 10. A reference clock is added and subtracted by this output at a lag/lead phase control circuit 9 to generate a clock signal controlling a hopping pattern generator 11. A synchronizing pulse is generated at a bisecting point of the area of the asynchronous part in place of the synchronous part by the intervention of an inverting circuit 6. |
