GB1270729A - Missile target seeker arrangements - Google Patents

Abstract

1,270,729. Missiles. TELEFONAKTIEBOLAGET LM ERICSSON. 17 Dec., 1969 [19 Dec., 1968], No. 61570/69. Heading F3A. [Also in Divisions G4 and H4] A missile target selector comprises a receiver connected to an antenna, a video quantizer connected to the receiver and feeding a counter which counts the number of quantized video pulses received while the antenna scans through a predetermined angle, wherein at the end of said angle scan a number generator chooses an arbitrary number less than or equal to the content of said counter and the antenna then rotates in the opposite direction and stops on a target indicated by said arbitrary number. Echo signals are processed in quantizer 4 which produces pulses of constant amplitude and length, the number of pulses being determined by the echo pulse length. These pulses are counted by an analogue or digital counter 7 which provides an output to a comparator 9, the second input to which is the output of a fast running counter 8. When the comparator inputs are equal, it provides a pulse which resets counter 8 to zero and starts it counting again. When the antenna has scanned through the predetermined angle counter 8 is stopped and is thus at a number less than or equal to the number of targets detected. Counter 7 is now reversed and counts down as the antenna rotates backwards. When the comparator inputs are again equal the antenna is stopped and the missile is locked on to that particular target. In a second embodiment, after the arbitrary number has been chosen as before, counter 7 reset to zero at every transmitter pulse as the antenna scans backwards. Before resetting the counter 7 content is subtracted from the counter 8 content and when these are equal the antenna stops. Units 5, 6 are provided to detect either single or group targets and place the range gate pulses accordingly.