Comparison of Sequential Decoding and Direct Decoding of LDM in Next-Generation Digital Terrestrial Television Broadcasting

抄録

In Japanese next-generation digital terrestrial television broadcasting(DTTB) for ultrahigh-definition television(UHDTV) broadcasting, the application of the layered division multiplexing-band segmented transmission-orthogonal frequency division multiplexing(LDM-BST-OFDM) transmission scheme is studied. Sequential decoding and direct decoding are proposed as decoding schemes. In addition, gray mapped LDM(GLDM) is also proposed as a mapping scheme. Reception Performance of sequential decoding and direct decoding have not yet been compared. GLDM and normal LDM have also not yet been compared. In this paper, Sequential decoding and direct decoding against the lower layer(LL) required carrier-to-noise ratio(CNR) of the LL are discussed. As seen from a computer simulation, the reception performance of direct decoding is better than that of sequential decoding in some cases, where the required CNR of LL is smaller than that of upper layer(UL) in direct decoding. In addition, GLDM can improve reception performance compared with normal LDM when direct decoding is used in LDM.