One thing to be aware of with analog wireless is that a high RF noise floor can cause a high audio noise floor.
This requires a bit of elaboration: In FM systems, as long as the carrier to noise ratio at the receiver is better than 12dB, the receiver will be fully captured and the RF noise floor is irrelevant; it will not affect the audio noise floor. Only once the CNR decreases to below 12dB will the RF noise floor contribute to audio noise after demodulation.
In AM systems, RF noise and demodulated audio noise are proportionally related, but with modern DSP, the audio noise can be kept at bay until a CNR of about 15dB.
