地上ディジタル放送におけるOFDMシンボル長とスキャッタードパイロットによる伝送特性(<論文小特集>ディジタル伝送)

概要

論文の詳細を見る
Orthogonal Frequency Division Multiplexing (OFDM) is a prime candidate for use as a modulation method for digital terrestrial broadcasting, because it is robust against multipath interference and can be demodulated correctly under Single Frequency Network circumstances. Mobile reception or HDTV broadcasting can be achieved by using DQPSK or 64 QAM modulation, respectively, as the carrier modulation method for OFDM. When a receiver demodulates 64 QAM, pilot symbols are necessary as amplitude and phase references. This paper describes a study on how transmission performance depends on symbol duration for mobile reception, and on the frequency, time intervals, and level of pilot symbols. The results show that a 500 μs OFDM symbol duration can support mobile reception in the case of DQPSK-OFDM. It is suitable for the pilot symbols to have a frequency interval of 3,time interval of less than 5,and a data symbol level of 1.2 to 1.4 times that of the average level of data symbols.
社団法人映像情報メディア学会の論文
1998-11-20