I recommend housing the switching converter in a separate module. It is going to put out EMI which will wreak havoc with circuitry that has to read RF signals.I have decided to go with a switching regulator, due to the heat cause by a linear regulator.
You can't believe how many hours I spent in an EMI chamber fighting with switchers to get them to meet the EMI limits needed for a given certification. That is a real nightmare. Hope you have an engineer who is versed in the art.
BTW: you can buy one of these for about $3.