A study on Digital Terrestrial Broadcasting System in SFN : The transmission characteristic of re-broadcast relay networks

Abstract

Transmission characteristic of OFDM signal through cascaded re-broadcasting relay stations in a SFN are studied. In each relay station, the signal is degraded due to a coupling from transmitting antenna to receiving antenna. To keep a bit error rate 10^<-3> or less at the reception in the fifth relay's area for example, the coupling signal ratio at each relay station should be suppressed less than -18dB for C/N=30dB. In a particular case that coupling delay signals of each relay station is very closed, transmission characteristics of OFDM signal vary drastically depending on coupling phase ; BER varies better the order 10^<-4> to 10^<-2>.