As is said on this page: "The Windows Phone Emulator does not have any built-in support for testing Proximity, requiring you test your NFC functionality using a Windows Phone 8 that supports NFC." and "Bluetooth cannot be tested using Windows Phone Emulator."
I'd suggest to test your code on actual device, otherwise you might not be able to to debug your app properly.
Proximity for Windows Phone 8
http://msdn.microsoft.com/en-us/library/windowsphone/develop/jj207060(v=vs.105).aspx