Study on Secure Voice Communication Technology over 3G Network
Hongbin Liang · Communications technology · 2010
Through studying the technical standards of 3G system and analyzing the 3G-related service processes,this thesis discusses 3 secure voice communication modes for 3G system,including TrFO(Transcoder Free Operation)mode,speech-like mode and VoIP mode.Moreover,the thesis describes the transmission process of secure voice in each mode.Bt using speech-like mode and VoIP mode,the TD-SCDMA secure cellphone is developed,thus the secure voice communication over 3G network(TD-SCDMA)successfully implemented and good voice quality in these two modes acquired.However,the realization of secure voice communication in TrFO mode would rely on the implementation of TrFO function.