Integer linear programming in CVX

I want to use CVX to solve antenna selection problem. An integer programming problem is formulated, and I defined an diagonal activity matrix S, whose diagonal elements is 0-1 integer.
The selected channle matrix Hs can be expressed as:Hs=H*S
Then ZF precoding W is applied: W=Hs'*inv(Hs*Hs')
My matlab code is as follows:

    variable s(Nt) 
    S=diag(s);
    W=(hmat*diag(s))'*inv((hmat*diag(s))*(hmat*diag(s))');  

But matlab reports an error:

    Disciplined convex programming error:
    Only scalar quadratic forms can be specified in CVX

So how can I modify the precoding matrix W after antenna selection in CVX?

I marked this as non-convex; which of course it trivially is because of the integer constraints. Nevertheless, W does not satisfy the DCP ruleset even if the binary constraints on S are relaxed, so it does not satisfy the DCP rules. Please read the FAQ.

I admit that the error message here is less than helpful, but the inv is not legal either.

Bottom line, CVX will not be able to solve your problem.

Thanks for your help!

And of course, if there really were an integer linear programming problem (as stated in the title), it could be formulated in CVX. It is not linear.