一种有效的MIMO OFDM信道估计方法

传统的MIMO OFDM信道估计方法总是假设信道在由若干OFDM符号组成的每一帧的传输过程中保持不变,但这个假设在快变信道的条件下就不成立了.本文提出了一种适合快变信道的有效的估计方法.该方法通过在每个OFDM符号中设置若干训练子载波来跟踪快变的信道.首先讨论了在每个OFDM符号中所需的训练子载波的数目及其相应的位置,给出了在多发射天线多接收天线条件下的训练子载波的正交结构,然后在估计出训练子载波处的信道频率响应后.提出了一种不同于根据邻近训练子载波进行线性插值的以获得用于传输数据的子载波的信道频率响应的方法.仿真结果表明了我们所提出的方法的有效性.

An Efficient Channel Estimation Technique in MIMO OFDM Systems

Conventional channel estimation techniques for MIMO OFDM systems always assume that the channel state is static during the transmission of a frame composed of OFDM blocks.But it isn't true in fast-varying channel situation.In this paper,an effi- cient channel estimation technique suitable to fast-varying channel is proposed.We use a set of pilot tones in each OFDM block in order to track the fast-varying channel.The number of pilot tones in each OFDM block and their arrangement are first discussed,and the or- thogonal structure of pilot tones is proposed under the condition of multiple transmit antennas and multiple receiver antennas.Then after the estimation of the channel frequency response of pilot tones,to obtain the channel frequency response of data tones,a new interpolation method different from linear interpolation method according to adjacent pilot tones is proposed.Simulation results have shown good per- formance for the technique.