VOICE SCRAMBLER APPLYING INVERSION OF FREQUENCY

摘要

PURPOSE: To provide a voice scrambler which applies the inversion of frequency and requires no high-order LPF. ;CONSTITUTION: A voice scrambler consists of a pair of phase shift circuits 2 and 3 which relatively shift the phases by 90° against an input signal, a pair of both side band signal generators 4 and 5 which receive the output signals of both circuits 2 and 3 and produce the both side band signals, an adder means 6 which adds together the output signals of both generators 4 and 5 and attenuates the upper side band signal USB, and an LPF 7 which receives the output signal of the means 6 and attenuates the remaining upper side band signal.;COPYRIGHT: (C)1994,JPO&Japio