DEVICE FOR DECODING MULTI-FREQUENCY SIGNALS Russian patent published in 1995 - IPC

FIELD: radio engineering. SUBSTANCE: device has filter 1, comparator 2, register 30, delay element 7, four counters 5,9,16,18, two AND elements 3 and 8, two OR element 11 and 15, comparing unit 14, distributor 22, and subtracting unit 13. In addition, device has unit of AND elements, five OR elements 17,19,21,26,31, two AND elements 4 and 25, unit of AND-OR elements 23, switch unit 27, unit of OR elements, unit 10 for initial setting, unit 6 for dividing frequencies, and two delay elements 20 and 24. EFFECT: enhanced noise immunity. 1 dwg