Performance evaluation of the ISDB-T standard for multimedia services

The Integrated Services Digital Broadcasting Terrestrial (ISDB-T) standard is one of the three dominant digital television terrestrial broadcasting standards. It employs concatenated coding and OFDM techniques to combat fading and multipath channel impairments. ISDB-T operates in 6, 7, or 8 MHz channel bandwidths, with each channel supporting up to three different services. These services may use different convolutional code rates, modulation schemes, and time interleaving lengths to meet different quality of service requirements. In this thesis, an ISDB-T baseband simulation model is implemented using SPWTM, C, and C++, and validated. This model is built to accommodate all of the possible ISDB-T system configurations. Since the target BER in ISDB-T is very low, for example, 1x10 1 1 for high definition television, it is impractical to obtain the BER directly using software simulation. A Markov chainbased semi-analytic method is used, which agrees well with available simulation results in nonfading environments. The semi-analytic results are quite different from the simulation results in fading channels, especially at very low Doppler frequencies. The channel undergoes deep fades at very low Doppler frequencies, causing a large number of symbol errors during these fading periods. The Markov chain model does not model these kinds of long error bursts very well. A numerical analysis is provided for very slow Rayleigh fading. The results of the numerical analysis agree quite well with the simulation results.