Institute of Electrical & Electronic Engineers
In this paper, the Filter-and-Forward (FF) relay design for OFDM communication systems is considered to enhance the system performance over the conventional Amplify-and-Forward (AF) relaying scheme. The considered design criterion in this paper is to maximize the worst subcarrier channel Signal-to-Noise Ratio (SNR) subject to the total relay transmit power constraint in order to improve the overall transmission quality-of-service. It is shown, by exploiting the eigen-property of circulant matrices and the structure of Toeplitz matrices that the considered problem reduces to a Semi-Definite Programming (SDP) problem. Numerical results are provided to validate the authors' design method and the numerical results show that the proposed FF relay outperforms the AF scheme significantly.