For the traditional received signal model $y=hx+n$, the channel coeficient is usually considered as complex number.
But when analyzing the motivation for the Alamouti space time coding scheme here using real channel coeficient, the motivation become very easy to understand and extremely simple.
This just motivate me to use real channel coefficient for understanding communication system to get the gist more easily.
Therefore, my questions are
1/ When can we use real channel coefficient instead of complex one to understand communication scheme ?
2/ Are there any pitfalls to this way of thinking
Thank you for your enthusiasm !