Techniques forEnsuring Co-existence BetweenB-VHFandLegacy VHF Systems
Sinja Brandes, Michael Schnell · 2015
Apromising approach forfuture airtraffic controladditional data services inaseparate frequency range, which (ATC)isthemulti-carrier based broadband communication requires thedevelopment ofanewdatacommunication sys- system B-VHFoperated intheveryhighfrequency (VHF) temappropriate forthat frequency range. However, thelong- band. Inorder toallow foragradual in-band transition from termsolution isanewcommunication system whichsatisfies thecurrent toafuture ATCcommunication system theB- theincreasing demandoffuture voice anddata communica- VHFsystem usesanoverlay concept, i.e., theB-VHFsystem tion systems forATM andATC.Duetothegoodpropaga- coexists withthecurrent VHFcommunication systems inthe tion conditions intheVHFbandthenewsystem should also samefrequency banduntil theoperation ofthecurrent VHF beapplied inthat frequency band.Thisrequires anin-band systems hasphased out. Thetwomainissues tobesolved for transition phase inwhichthecurrent andthefuture commu- asuccessful co-existence aretheavoidance ofinterference nication system workinparallel. Onecandidate forfuture fromtheB-VHFsystem tothelegacy VHFsystems andthe aeronautical communications istheso-called broadband VHF suppression ofinterference fromthelegacy VHFsystems at (B-VHF) system (1). TheB-VHFsystem isdesigned asan theB-VHFreceiver. Therefore, existing aswell asnewmeth- overlay system based onorthogonal frequency-division mul- odsforthereduction ofout-of-band radiation oftheB-VHF tiplexing (OFDM). Thisconcept hastheadvantage that an transmit signal areproposed andinvestigated. Moreover, sev- in-band transition phase canberealized asthecurrent VHF eral efficient concepts areanalyzed whichmitigate different systems andthenewB-VHFsystem coexist inthesamefre- kinds ofinterference attheB-VHFreceiver. Simulation re- quency band. However, toenable suchacoexistence mutual sults showtheappropriateness oftheproposed schemes. interferences between thesystems havetobereduced which isthetopic ofthis paper.