A study on block equalization for OFDM systems with short Cyclic Prefix

In this paper, we propose a new Cyclic Prefix (CP) design for Orthogonal Frequency Division Multiplexing (OFDM) system with higher tranmission efficiency. The proposed signal design concatenates some OFDM symbols without guard interval and adds one CP per the concatenated symbols. Obviously, the proposed CP design results in severe inter-symbol-interference and inter-carrier-interference when we apply the conventional OFDM demodulation to the received signal. In order to combat them, we introduce the frequency domain equalization technique with the maximum ratio combining, zero forcing and Minimum Mean Square Error (MMSE) filters. By computer simulations, we show that the proposed system with the MMSE filter owing to the diversity effect outperforms the conventional one.