| 摘要 |
<p>1520537 Pulse doppler radar NISSAN MOTOR CO Ltd 11 Nov 1976 [11 Nov 1975] 47049/76 Heading H4D A noise-immune IF signal processing circuit 18 in a pulse doppler radar for mounting on a vehicle includes comparators 21, 22, for generating output signals when the positive and negative half waves of the IF signal reach threshold values, a bi-stable device (flip-flop) 27 responsive to said signals, feedback circuits via resistors R5, R6, for varying the positive and negative thresholds in accordance with the binary state of device 27, and means allowing the passage of one of the output signals that occurs earlier than the other output signal to the device 27 and preventing said other output signal until the order of occurrence of the output signals is reversed, see Fig. 3 (not shown). This latter means comprises a second bi-stable device 24 which receives trigger signals over line 33 as well as the output signals from comparators 21, 22, via OR gate 23.</p> |
