Title :
The digital voice terminal for slow-FH radio application
Author :
Miyake, M. ; Naitoh, Masataka ; Watanabe, Osamu ; Matsumoto, I.
Author_Institution :
Kokusai Electr. Co Ltd., Sendai, Japan
Abstract :
The authors present a real-time digital voice terminal (DVT) for slow frequency-hopping (slow-FH) radio applications to ensure a reliable radio link. Slow-FH technologies have been introduced for ECCM communications as a near-term solution which will not disturb the usage of the present conventional radio spectrum. Digital secure algorithms with digital speech codec are known to achieve a high degree of security. The DVT is composed of a speech codec and a voice-band modem. The speech codec that is used for the DVT is a 4.8 kbit/s pitch predictive coder using adaptive transform coding (PP-ATC). The modem is a QAM voice-band modem. This modem has a specific signal format to allow waveform shaping by a hopping transmitter to keep RF compatibility with conventional radio. The authors address aspects of the DVT architecture, the implementation of algorithms in the signal processors, and the system performance
Keywords :
codecs; digital communication systems; electronic countermeasures; encoding; frequency agility; modems; radio applications; radio links; speech analysis and processing; 4.8 kbit/s; ECCM communications; QAM; RF compatibility; adaptive transform coding; digital secure algorithms; digital speech codec; hopping transmitter; pitch predictive coder; radio link; radio spectrum; real-time digital voice terminal; signal processors; slow frequency-hopping; slow-FH radio application; system performance; voice-band modem; waveform shaping; Electronic countermeasures; Frequency; Modems; Quadrature amplitude modulation; RF signals; Radio link; Security; Signal processing algorithms; Speech codecs; Transform coding;
Conference_Titel :
Military Communications Conference, 1991. MILCOM '91, Conference Record, Military Communications in a Changing World., IEEE
Conference_Location :
McLean, VA
Print_ISBN :
0-87942-691-8
DOI :
10.1109/MILCOM.1991.258451