传输损耗条件下基于循环平稳检测的空时分组码盲识别方法

针对传输损耗条件下空间复用（SM）和Alamouti空时分组码的盲识别问题，提出一种单接收天线下的基于循环平稳检测的盲识别算法。首先通过理论推导，证明Alamouti空时分组码具有循环频率的特性；然后，求取接收信号的四阶循环累积量来观察循环频率；最后使用循环平稳检测的方法，构造检测不同空时分组码循环频率的假设检验，从而对2种码的接收信号进行区分。该方法可在单接收天线下进行，蒙特卡洛仿真结果表明，该算法不需要预先知道信道信息、调制方式、载波相位和时间偏移，不需要精确知道载波频偏，识别效果较好。

Blind Recognition for STBC with Transmission Impairments Based on Cyclostationarity Test

An algorithm is proposed based on fourth-order cyclostationarity to classify Spatial Multiplexing (SM) and Alamouti space-time block code (STBC) with transmission impairments when a single antenna is employed at the receiver. Firstly, we prove the feature that Alamouti STBC signals hare cyclic frequency. Secondly, the fourth-order cyclic cumulants of the received samples are calculated to observe the cyclic frequency. Thirdly, we exploit the discriminating features provided by cyclic frequency of different STBCs, and construct cyclostationarity test to detect the cyclic frequency to achieve the classification. The algorithm can work in single received antenna scenarios. Monte Carlo simulation shows that the algorithm does not require the channel state information, modulation of the transmitted signal, carrier phase and time offset. It does not need to accurately know the carrier frequency offset and performs well.