Decrease Xbee transmission range

Hi everyone

I have bought several Xbee 1mW wire antenna modules. My problem is quite an uncommon one: I need to reduce the transmission range to be at most 3-5 meters. Using the lowest transmission power, the modules still can achieve a transmission range of more than 15m (indoor, line of sight).
What I mean as transmission range is the separation distance which allows two modules to transmit data with good PRR (Packet reception rate at least 75%).
I tried wrapping the modules in aluminum foil, but I am looking for a more “technical” ways (e.g. replacing, removing or cutting the antenna?)



I don’t know of any clever ‘official’ way to do this.

I suppose you could cut off the WHIP wire antenna, or not install a U.FL or RPSMA antenna. You’d have limited control of the result.

If you wanted to experiemnet, I’d suggest the U.FL XBEE with various pieces of ‘wire’ - might give you some control but I can’t suggest how one equates wire-length to strength.

For internal testing, I know Digi uses some u.FL XBee which wire into PCB traces with antenuators to do dynamic testing with adjustable signal strength.