Aerial in rear windscreen

[CJ]

Those of you with aerials built into the rear windscreen will know that bad radio reception can be a problem at times, I came cross this thread on a BMW forum which decribes the same problem, theres is talk of fitting a surpressor and uprated aerial amps to fix the problem but not much on how this can be achieved. I'd be interested to hear from anyone who could shed light on this area. (No comments about the power antenna lead not being connected up )

CJ