hat
Se transmisyon an ki baze sou kode Orthogonal Frekans Divizyon Multiplex (COFDM). COFDM itilize yon gwo kantite transpòtè. Chak nan transpòtè sa yo se itilize transmèt sèlman yon pòsyon nan kantite total de done yo. Done a module sou transpòtè yo ak QPSK oswa QAM. COFDM gen avantaj ke li trè gaya kont resepsyon multipath ak frekans selektif manyak. Sa a se solidite kont resepsyon multipath jwenn nan sèvi ak yon 'entèval gad palè'. Sa a se yon pwopòsyon nan tan an pa gen okenn done transmèt. Entèval gad sa a redwi kapasite transmisyon an.
eng
The transmission is based on Coded Orthogonal Frequency Division Multiplex (COFDM). COFDM uses a large number of carriers. Each of these carriers is used to transmit only a portion of the total amount of data. The data is modulated on the carriers with QPSK or QAM. COFDM has the advantage that it is very robust against multipath reception and frequency selective fading. This robustness against multipath reception is obtained through the use of a 'guard interval'. This is a proportion of the time there is no data transmitted. This guard interval reduces the transmission capacity.