Abstract :

A spectrally efficient digital modulation mechanism in which multiple carriers are present that are mutually orthogonal to each other over particular time is known as Orthogonal Frequency Division Multiplexing (OFDM) system. A subcarrier is known as a carrier in which a pair of sine wave as well as cosine wave is involved. Even though there is an overlap of the sidebands from each carrier, there is no interference involved within the signals that are received here since they are orthogonal with respect to each other. The carrier spacing that is equal to reciprocal of the symbol period is used here. The bit error rate is the major issue of OFDM due to dynamic nature of the network. The space-time trellis coded is the extra codes which reduce bit rate error over the multipath fading channel. This research work is based on wireless channel to reduce bit error rate using space-time trellis codes. In this research work, the bit error rate is reduced over the wireless channels using space time trellis codes and KALMAN filters. The simulation of the proposed modal is performed in MATLAB and results show that bit error rate is reduced in the network.