| 摘要 |
PURPOSE:To detect the number of pulses following one leading pulse by judging an n-let PRI (Pulse Repetition Interval) pattern signal in real time from the frequency distribution of pulses to time intervals. CONSTITUTION:From a string of pusles input to input terminal 1, a leading pulse with an assigned pulse interval is extracted by using the 1st PRI filter circuit 3. Similarly, the 2nd PRI filter 4 is used to extract pulses following the leading pulse. Here, the number of pulses input within a certain time is denoted as Z, the number of the leading pulses within the certain time is denoted as X, and the number of pulses following the leading pulses is as Y. Then, number N of pulses following one leading pulse is found from N=Y/X. Then, when Z<=S1, X+Y>=Z.S2 and N>=1 for the 1st normal value S1 and the 2nd normal value S2 (<=1), an n-let type PRI pattern signal is judged. |
