cross_corr_error

代码说明：

  Clarke模型的提出代表了Rayleigh分布用于平坦小尺度衰落统计模型的开端。虽然因为其实现比较复杂，而更倾向于被认为是一种数学模型而非仿真模型，但所涉及到的Rayleigh衰落信道的概念是其后众多改进模型的基础(The Clarke model put forward on behalf of the beginning of the Rayleigh distribution for flat small-scale fading statistical model. Because its implementation is more complex, and more inclined to think that instead of the simulation model is a mathematical model, but involved in the Rayleigh fading channel concept is the basis of many subsequent improvement model)