导频符号调制方式对OFDM信道估计的影响(英文)

Influence on OFDM Channel Estimation by Modulations of Pilot Symbol

引入了基于线性变换的正交频分复用信道的频域估计方法,通过对接收信号的线性变换达到数据的有效恢复。首先推导了关于推广后旋转矩阵的两个性质定理;然后根据所得的旋转矩阵的性质,给出了导频符号分别基于BPSK和QPSK调制的两种OFDM信道估计算法。在假设信道为瑞利衰落并且在一帧内保持不变的情况下,对基于这两种信道估计算法的系统进行了仿真比较。仿真结果显示,当各子载波的同相信道和正交相位信道同时插入信道估计符号时,OFDM系统的误码率和误包率都可以得到明显的改善。

A frequency-domain channel estimation （CE） scheme for orthogonal frequency division multiplexing （OFDM） channel estimation which is based on a linear transformation is developed. The transmitted signal can be recovered efficiently by a linear transformation of the received signal. Firstly, two results on the generalized rotation matrix are deduced. Then based on the modulations of pilot symbols BPSK or QPSK, we achieve two channel estimation algorithms respectively. Simulations are performed at the condition that the channel is assumed to be Rayleigh fading and fiat within one frame. Simulation results show that the BER and PER performance can be improved obviously when in-phase channel and quadrature-phase channel of each sub-carrier are inserted in the pilot symbols.