Hi,
Depending on the current drawn by the logic side, if it's in the low milliamp range maybe you could use an **broken link removed** instead of the diode only bridge rectifier.
You can cut "defensive" horseshoe shapes around the MOSFET pins that concern you to sort of isolate noisy return paths from the main ground (and therefore antenna ground), if that's what you mean, or make a horrendous slit across almost all of the middle of the board or wherever is appropriate to "separate" both sections, ...but nowadays I don't think analog and digital grounds are really separated that much.
I imagine if one looked hard enough, one may find op amp circuits that create a virtual ground, but not so sure about this last suggestion being factual.