Abstract: Digital video broadcasting – Terrestrial standard as the one which actually is modifying the existing analog standards existing currently across the globe. The most important part of such standards is the retrieval of perfect signal at the receiver end excluding the effects of the channels it goes through and the noise and timing jitter. In the transmission being carried out, the data – either audio – video or any picture information or randomized data is processed for Coded Orthogonal Frequency Division Multiplexing (COFDM) before they are modulated using QAM – Quadrature Amplitude Modulation constellation and mapped in the group of blocks. After formation of the blocks, IFFT – Inverse Fourier Transform is carried out with point 2048 or 8192, which will determine bandwidth requirement and number of subcarriers. Some of these subcarriers are kept in reserve to be used for the pilot symbols – much needed for efficient reception of the signals, whereas the others are to be used for guard bands as well. Though there are many virtues of implementing DVB-T system, there are many shortcomings too of the same which cannot be neglected. The very first limitation and an important one too, is in the form of bit error rates supported by it. They are limited and not compatible with the existing and rapidly changing wireless standards. For the transmission of HDTV – high-definition television and also for accommodating more channels for broadcasting, there was a strong need of new standard. The second limitation of the DVB-T system is its hugely inferior performance with portability or mobility which restricted its usages in moving vehicles.
Keywords: DVB-T, OFDM, BER, RS
| DOI: 10.17148/IJIREEICE.2019.8105