应用在OFDM-MIMO系统的低复杂度时域导频方案

提出了一种应用在正交频分复用多天线系统的时域导频方案.该方案能获得较高精度的均方估计性能,导频与有用数据无干扰,且计算复杂度低,多天线场景下,信道估计的性能不受传输天线个数的影响.相比最小二乘估计,该方案只需要对接收信号进行简单的线性相关运算,配合特定的系统参数,能获得较大的信噪比增益;相比线性最小均方误差估计,其仅利用了信道长度信息,性能渐近最优,能获得估计性能与复杂度的折中.

A Low Complexity Time Domain Pilot Scheme for OFDM-MIMO Systems

The performance of a low complexity time domain pilot scheme for orthogonal frequency division multiplexing-multiple input multiple output systems is analyzed. The scheme is turned out to be of relatively high estimate accuracy with low calculation complexity, and the estimate performance is unaffected with numbers of transmit antenna. There exists no interference between pilots and data symbols. Compared with least square estimator in frequency domain, the present scheme can obtain gains with specific parameters and simple linear correlation under the same mean square estimation level. Also compared with linear minimum mean square error (LMMSE) estimator, the scheme approximates the optimization of LMMSE's favorable performance in high signal to noise ratio region with knowledge of channel taps length only and no more priori information in the estimate process.