| 摘要 |
PURPOSE:To strengthen a privacy communication function by generating dummy data at the time when a transmitting output at the time of switching a frequency is disconnected, synthesizing the dummy data and an enciphered input sound signal and inputting them to a frequency hopping radio equipment. CONSTITUTION:When an FH timing (k) is inputted to a timing generator 27 from a frequency hopping(FH) radio equipment 12, a voice encoder 21 encodes a voice input signal (a) by a voice analytic frame signal (g), and outputs it to a frame signal generator 23 as cipher voice encoding processing data (e) through an encipherer 22. Also, a dummy data generator 26 outputs dummy data (i) by a timing signal (m). In the generator 23, the data (e) and (i) are synthesized, and composite data (j) is outputted to the radio equipment 12 through a modulator 24. Moreover, when the time when the data (i) is outputted and the time when an output (c) of the radio equipment 12 is disconnected at the time of execute FH are allowed to coincide with each other in advance, no influence is exerted on necessary voice data. In such a way, a privacy communication function of a low speed digital FH communication system can be strengthened. |
