What is a Diversity Antenna Module?

[RiffRaffMama]

Looking at anti-theft alarm info in a manual I came across this image showing the various control modules in VT-VY cars and I'm perplexed by this "diversity antenna module". I can't find any references to it online in relation to Commodores. What does it do?

 

[lmoengnr]

It uses 2 separate FM antennas to try and avoid multipath distortion.

 

[Nut Kracker]

Here's a detailed explanation....