Channel estimation using MMSE based DFT for OFDM system

OFDM (Orthogonal Frequency Division Multiplexing) is a multicarrier technology that divides high-speed data rates into parallel low-speed data rates by dividing the signal into n- orthogonal subcarriers and overlap. Channel estimation problems are also very important in a communication system for better system performance. Channel estimation is a process to determine the characteristics of a channel that aims to get the received data close to the transmitted data. This paper discussed Orthogonal Frequency Division Multiplexing (OFDM) as a modulation technique that can minimize the effect of Inter Symbol Interference (ISI) caused by multipath on a channel. In addressing this problem, channel estimation is needed to determine the channel condition by inserting a pilot into the data that has been sent. In the process, the MMSE (Minimum Mean Square Error) method is used. A DFT-based addition aims to improve channel estimation performance by eliminating noise outside the maximum channel delay and the accuracy of the transmitted approach to the information signal. System performance results are displayed by comparing the Bit Error Rate (BER) curve to the Signal Noise Ratio (SNR), as well as the comparison of the estimated MSE (Minimum Square Error) channel values with and without the addition of DFT.