Radio Locator system for a warehouse

[Marktecwiz]

I am building a system that detects when a mobile Radio attached to a pallet is place in one of 15 locations in a large warehouse.  My idea is to program an moteino that would be in the fixed locations so that it sends out a very low power quick serialized beacon every 5 seconds.  The mobile tag that is attached to the pallet would be programmed to listen for the beacons and then report back to a base station the beacon serial number that the mobile radio is near.

I plan to use 915 mhz devices for longer range from the mobile tag to the base station.  I also plan to lower the power of the beacon either with software or smaller antenna (detuned if necessary).  If the tag receives two beacons it would determine the closer one using the RSSI of the message.

Does anyone have experience in setting up a system using multiple beacons and lowering the power of the beacons to detect when you are by the beacon with a second radio?

Thanks in advance

[Felix]

Your listening nodes will take more power (about 15.5ma if you sleep the micro and keep the radio in RX mode). That is a lot if you battery power. I would probably invert the scheme and have the mobile ones transmit then sleep most of the time. I think it would be much the same, but I do follow your logic of having the fixed stations emit (and try to control how far they transmit).
You can just use the setPowerLevel(1-31=max) function to decrease their output power (use W radios not HW since you don't need max power anyway).
Using my inverted scheme I suggested, I think your mobile nodes would then also transmit (in broadcast mode) at low power output, every few seconds (?) and then sleep most of the time. Your base units would listen (perhaps in promiscuous mode to receive any packet from anyone going to anyone on same network).