EFFECT OF TIME INTERLEAVING PARAMETERS IN MOBILE DVB-T2 SYSTEMS

DVB-T2 is an abbreviation for Digital Video Broadcasting– Second Generation Terrestrial.It is the extension of the television standard DVB-T. DVB-T2 succeeds in achieving the reception quality and a capacity increase of 50% over its predecessor DVB-T. This system transmits compressed digital audio, video, and other data using physical layer pipes (PLPs),using OFDM modulationtechnique (modes of 1k, 2k, 4k, 8k, 16k, and 32k)with concatenated channel coding and interleaving. DVB-T2 implements a very flexible time interleaving that allows multiple tradeoffs in terms of time diversity, latency and power saving. In this paper, we study in detail these tradeoffs in the context of mobile reception.. In addition, we propose the utilization of upper layer FEC protection in order to overcome the limitations of the DVB-T2 physical layer for the provision of long time interleaving, and enable fast zapping. Using this UL-FEC we can get gains up to 4 dB to 9 dB in highdiversity scenarios.FEC is concatenated low density parity check code(LDPC) and BCH codes (as in DVB-S2 and DVBC2), with rates 1/2, 3/5, 2/3, 3/4, 4/5, and 5/6.The performance is evaluated by means ofcomputer simulations. For the simulations we have used a configuration of 64QAM, code rate 1/2 and maximumsub-slicing. Our investigation shows that the utilization of sub-slicing is highly beneficial in fast fading scenarios.