I have always have a problem to solve the following question

```
cvx_begin sdp quiet
variable W(Nt,Nt,Rx) hermitian
variables a t211 r111 r211 t212 r112 r212 t121 r221 r121 t122 r222 r122 t21 ra1 ra2 t11 rb2 rb1
sum=0;
for f=1:Rx
sum=sum+W(:,:,f)
end
min sum
subject to
A=[W(:,:,1)-a*z*W(:,:,2)+r111*eye(2),(W(:,:,1)-a*z*W(:,:,2))*h111;h111'*(W(:,:,1)-a*z*W(:,:,2)),h111'*(W(:,:,1)-a*z*W(:,:,2)-z*a*t211-z*a*sigmma-r111)]
A1==hermitian_semidefinite(3);
cvx_end
```

error:

```
Error using ==> cvx.times at 262
Disciplined convex programming error:
Invalid quadratic form(s): not a square.
Error in ==> Untitled3 at 64
A=[W(:,:,1)-a*z*W(:,:,2)+r111*eye(2),(W(:,:,1)-a*z*W(:,:,2))*h111;h111'*(W(:,:,1)-a*z*W(:,:,2)),h111'*(W(:,:,1)-a*z*W(:,:,2)-z*a*t211-z*a*sigmma-r111)];
```

please help me