Why the cvx_optval is Inf and the cvx_status is Unbounded

cvx_begin
         variable W(Nt,Nt,KI) complex
         for i=1:KI    
              power(i) =  real(trace(G*W(:,:,i)));
              R1(i) = real(trace(W(:,:,i))) ;
              R2(i) = real(trace(L'*L*W(:,:,i)));       
         end
         maximize sum(power)
         subject to
         sum(R1)<=10;
         sum(R2)<=10e-8;
         real(sum(W(:,:,i),3))>=0;
cvx_end
obj = sum(power);
cvx_cputime:2.093750000000000
cvx_optbnd:Inf
cvx_optval:Inf
cvx_slvitr:5
cvx_slvtol:1.490116119384766e-08
cvx_status'Unbounded'

Follow the advice in Debugging unbounded models - YALMIP , which also applies to CVX.