Channel estimation and training design for MIMO-OFDM two-way relay systems
The-Hanh Pham, Ying‐Chang Liang · 2012
In this paper we consider two-way relaying systems consisting of two end users, N1and N2, which exchange their information with the help of a relay, R. The three terminals are equipped with multiple antennas. The information exchange process between N1and N2are divided into two phases. Both N1and N2send their information to R at the first phase. The relay will amplify its received signals and transmit the resultant signals back to N1and N2at the second phase. The end users estimate the necessary channel coefficients to decode the signals; therefore, the processing burden on the relay is reduced. In this paper, a least-squared based estimation method is proposed to estimate those coefficients. Optimal pilot vectors are also proposed to minimize the mean-square-error (MSE) of channel estimation. Furthermore, the proposed training signals has the peak-to-average-power ratio (PAPR) of 1.