Uniquely identify a particular wifi source using Android devices

Question

I am working on an app that would allow indoor navigation using hardware devices that emit wifi signals in large public places such as hotels and hospitals. Each location would have multiple devices and each device would be unique so that we can identify the exact location of the device/person.

For this I don't want the user to connect to the wifi, if only a scan of the network was possible which could determine the current wifi beacon the mobile is closest to would do the job. I decided to use Android's WifiManager for the task:

WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
                    wifi.setWifiEnabled(true);

                   wifi.startScan() ;
                   List<ScanResult> mScanResults = wifi.getScanResults();
                   String s = "" ; 
                   for(ScanResult result: mScanResults){
                     Log.d("Wifi", result.SSID) ; 
                   }

None of the attributes for result seem to be appropriate for use as a UID for Wifi Beacon, I have two questions:

a) Can we use something like a BSSID for this purpose?

b) Can I write my own wifi manager class and then somehow negotiate a handshake with the wifi where it just tells me who it is without connecting? If so please share resources for doing the same.