Performance analysis of fast tracking equalization for SC-FDMA and OFDM systems under multipath fading environment

In this paper, SC-FDMA and OFDM systems with fast tracking equalizer based on RLS algorithm in multipath fading environments are proposed. In the proposed SC-FDMA and OFDM system with fast tracking equalizer, known-reference signals are allocated to the 1st slot of transmitting slots on each subcarrier at the transmitter. The transmitted signals are equalized with the reference signals on the frequency domain at the receiver. The channel information is updated by performing estimation based on RLS algorithm with the reference signals during the signal transmission, and the fast tracking equalization is performed. In order to confirm the transmission performance with fast tracking equalizer, computer simulations about BER and PAPR are carried out. As the results of computer simulation, the improvement of BER for the systems with equalizer based on LMS algorithm is about twice higher than the conventional system with only the initial equalization. Moreover, the improvement of BER for the systems with fast tracking equalizer based on RLS algorithm is about 3 times higher than the system with equalizer based on LMS algorithm. Furthermore, the advantage of PAPR in SC-FDMA system compared to OFDM systems is shown in computer simulation.