Location Tracking Using Zigbee mesh network

Hi..everyone..Im doing my final year project on location tracking using zigbee networks......Ok...this is my project..The zigbee module is connected to the computer and the zigbee module is connected to a PAN with the help of some zigbee routers..So the routers will be placed around the room ..the routers should track the the person with the rfid tag and send the information to the zigbee transceiver(module)..I need to somehow interface the rfid reader to the zigbee routers..So my doubt is
1) can i interface it directly to the router?..Or
2) Is there any zigbee router with the inbuilt reading capablity ( in order to reject the rfid reader )..?..
3) If not what micro controller can i use?..Also i need to buy the zigbee module and zigbee routers of range 15 to 20 meters...in order to avoid high cost..
4) So can anyone suggest me what module and routers can i buy?//////