| 摘要 |
1,199,644. Pulse radar. COMPAGNIE FRANCAISE THOMSON HOUSTONHOTCHKISS BRANDT. 30 Nov., 1967 [6 Dec., 1966], No. 54684/67. Heading H4D. A device, enabling a range-tracking radar to be automatically supplied with the correctlytimed strobe, is placed ahead of the integration stages 9, 11, Fig. 1, in the range-tracking loop and is effective when the radial acceleration of the tracked target exceeds a predetermined magnitude, the device including two identical and adjustable timed switches 34, 35, Fig. 4, each fed with a pulse train of instantaneous frequency proportional to the acceleration of the error signal from time discriminator 4 and each comprising a normally-closed switch which is opened by a control circuit on reception of the first pulse of the train and is closed on return of the control circuit to its initial state by either a pre-adjusted delay circuit triggered by that first pulse or by a reset circuit acting before the pre-adjusted delay has elapsed. The invention enables range-tracking to continue when two targets are at about the same range (and azimuth). In an embodiment the tracking acceleration error signal #r from amplifier 7, Fig. 1, is converted to a pulse train of frequency proportional to the absolute value of #r in a converter 31, Fig. 4, an acceleration pulse train is fed on line 32 to a switch 34, and a deceleration pulse train is fed on line 33 to switch 35. Each switch may consist, Fig. 2, of an input pulse train terminal 21 and an output terminal 22, pulses being removed from the input train by an opened contact 23 controlled by a relay 24; contact 23 is open when trigger circuit 25 is in the "1" position (i.e. "set") and is closed by a pulse to the "reset" terminal R; initially, contact 23 is closed, the first ensuing input pulse sets trigger 25 to open contact 23 which is closed once again by a pulse delayed by variabledelay circuit 26. Thus pulses which follow an output pulse by an interval less than that of the delay in circuit 26 are eliminated from the output. A signal at terminal 29 provides for re-setting of trigger 25 before the end of the delay of circuit 26. The delay is controlled such that when switch 35 or 36 has passed a pulse the switch opens for a time proportional to actual/predetermined acceleration; the delay may also be proportional to target range to allow for a manoevring target. |
