DigiMesh 2.4 modules - very short range

Hi -

We have a couple of these XBee 2.4 modules with the DigiMesh firmware. We can get them to communicate fine, but the range is only 20-30 feet. Firmware is 8003, Hardware version is 1741.

When I checked the power level, it was set to 4. Currently just typing back and forth in AT mode. These are the chip antenna modules.

We were looking at a house wide mesh of these for security and control, but can’t get enough range to leave a room at this point. Any suggestions? Thanks!

—Bill

I have searched here, but either there’s nothing specific to my situation or I don’t see it.

Hi Bill,

It seems like that your module is facing external interference like UV light, High Grid Power Supply in near by or Thick Cement Concrete wall in between two modules. Even with the chip antenna modules the range can be affected to little less than compared to U.FL or RPSMA or Wired.

This is in a home situation. The only interference I can think of might be WiFi APs. We have them plugged into little USB carrier boards then into two laptops. We’re seeing about -80dB signal strength across the same room, 20 feet apart. If I take it out the side door, only a drywall and siding external wall separates us. It starts dropping characters rapidly.

I will try shutting down the WiFi and see if it changes anything. Do the chip antennas need any additional ground plane to function?

Thanks!

—Bill

Why don’t you configure Channel frequencies for Wi-Fi and XBee both with some guard band between them?

XBee can be set to particular channel by SC parameter using bit mask.

Yeah, definitely not the WiFi - shut it down completely, no effect. Tried different channels, same.

We finally managed to get XCTU running, so we’re using the range check on there to do some more testing…

Another thing you could try would be to temporarily load the 802.15.4 firmware on one of the XBees. That gives you the ED, SC and SD commands (see the 802.15.4 product manual), which let you perform an energy scan on all channels. With X-CTU running on a laptop you’d then have a portable interference monitor which would probably give useful results more easily than a series of range tests.

Hi All,
I am also having the same problem. We have XBP24-BZ7WIT-004 63mW xbee modules modules and range is about 30m (out door with LOS). We have 2mW version of same modules, having much better range than these modules.

hi Bill, did you rectified your issue. Can you please share your experiments.
BR
SAM

Hi, I have a problem with range of XBee 802.15.4. I use the two regular XBee boards( not XBee-Pro) to communicate. They can talk each other; however, just within a range of 5-7 meters. I also run a range test but the range is not longer. I dont know the reason.
When I hooked the XBee board to Arduino board to control LEDs, the range is the same.
Is there anyone can help me out?
thank you so much!

These are radios, so the antenna design and ORIENTATION is important. For example, the ‘WIT’ Whip antenna jpksampath uses MUST be vertical to talk horizontally, as the RF radiation pattern goes outward from the wire. So 2 XBee with ‘whip’ antenna, where both point at each other will have very bad range.

Chip antenna also have a pattern, which I’m pretty sure is horizontal inline with the XBee PCB, so if you mount the XBee vertical, then your power goes up/down/left/right, but not front or back.