1 1 8 ; ▁ ▁Mobile ▁Information ▁Device ▁Profile , ▁JS R - 3 7 ; ▁ ▁W ire less ▁Mess aging ▁API , ▁JS R 1 2 0 ; ▁ ▁Con ne cted ▁Limited ▁Device ▁Configuration , ▁JS R - 1 3 9 ; ▁and ▁ ▁Technology ▁for ▁the ▁W ire less ▁Indust ry , ▁J TW I - 1 8 5 . ▁ ▁Com parison ▁between ▁T ET RA ▁and ▁Project ▁ 2 5 ▁▁ ▁Project ▁ 2 5 ▁and ▁T ET RA ▁are ▁util ised ▁for ▁the ▁public ▁safety ▁Radio ▁network ▁and ▁Private ▁S ector ▁Radio ▁network ▁world wide ▁however , ▁it ▁has ▁some ▁differences ▁in ▁technical ▁features ▁and ▁capac ities . ▁ ▁T ET RA : ▁It ▁is ▁optimized ▁for ▁high ▁population ▁density ▁areas , ▁with ▁spectral ▁efficiency ▁( 4 ▁time ▁sl ots ▁in ▁ 2 5   k Hz : ▁four ▁communic ations ▁channels ▁per ▁ 2 5   k Hz ▁channel , ▁an ▁efficient ▁use ▁of ▁spectrum ). ▁It ▁is ▁suitable ▁for ▁high ▁population ▁density ▁areas ▁and ▁Support s ▁full ▁du plex ▁voice ▁and ▁data ▁and ▁mess aging . ▁but , ▁it ▁is ▁generally ▁un available ▁for ▁sim ul cast , ▁ ▁V H F ▁band ▁- ▁however ▁particular ▁vend ors ▁have ▁introduced ▁Sim ul cast ▁and ▁V H F ▁into ▁their ▁T ET RA ▁platform .. ▁ ▁P 2 5 : ▁ ▁it ▁is ▁optimized ▁for ▁wider ▁area ▁coverage ▁with ▁low ▁population ▁density , ▁and ▁support ▁for ▁sim ul cast . ▁however , ▁it ▁is ▁limited