How to locate E field and H field null on patch antenna in Hfss

Dear friend, how can you make your question clear. Please help me out its urgent.

what i meant is after plot E field in HFSS, how to locate its null for short pinning purpose

You can create a non model object and place it on your antenna where you wanna see your E and H fields .....cut it out from the design( make sure you check the clone button) then plot the E and H fields over it. I done this before to see what mode of propagation I was in. I don't remember clearly, this was two years ago and I only did it once :p

Dear Jack,
thanx.
but how will this help me in locating E field null?