Through the comparison of the features of GSM and CDMA shortmessage services,the paper shows that the CDMA short messagecenter has stronger service capability a
1 OverviewTrunking communication is an importantbranch in the mobile communications area.By adopting the PTT(Push-to-Talk)mode,half-duplex single calls and grou
This paper analyzes threestandards forvideoconferencing andforecasts theirdevelopment trends.It isconcluded that ITUstandard H.320 can onlyvideoconferencinginvo