Consider a MIMO link for which the channel may be considered to be essentially "constant for k users of the channel."
a. Starting with the basic channel model of (9.105), formulate the input-output relationship of this link with the input being described by the Nr -by-k matrix
![686_Equation 01.jpg](https://secure.tutorsglobe.com/CMSImages/686_Equation%2001.jpg)
b. How is the log-det capacity formula of the link correspondingly modified?