# Xbee Pro 2SB XBP24-BZ7UIT-004 RSSI and range query

**URL:** <https://forums.digi.com/t/xbee-pro-2sb-xbp24-bz7uit-004-rssi-and-range-query/13935>\
**Category:** XBee - 802.15.4\
**Tags:** rssi, pro, range, 2sb, xbee\
**Created:** [November 17, 2014, 2:58am UTC](https://forums.digi.com/t/xbee-pro-2sb-xbp24-bz7uit-004-rssi-and-range-query/13935 "2014-11-17T02:58:55Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![nangdec](https://avatars.discourse-cdn.com/v4/letter/n/82dd89/32.png) [@nangdec](https://forums.digi.com/u/nangdec)\
**Post date:** [November 17, 2014, 2:58am UTC](https://forums.digi.com/t/xbee-pro-2sb-xbp24-bz7uit-004-rssi-and-range-query/13935/1 "2014-11-17T02:58:55Z")

</div>

Hi

I have three of these Xbee Pro modules with the UFL antenna connection.

I have used the Seeed studio UartSBee v5.0 to connect these via USB to computers.

I am using fairly generic 10cm long UFL to RPSMA pigtail cables to connect the Xbee modules to 5 dBi 2.4 GHz omnidirectional antennas.The pigtails have the sort of cable thickness you would see in a UFL cable inside a laptop.

I have set one module to be the coordinator and the other two to be routers.

When testing using a range test in X-CTU from the coordinator to either of the routers, the best RSSI I get is -76 dBM when the modules are 30 cm apart. When 4m away but still direct line of sight, I get around -91 dBM, i.e. only 1 bar of signal on the graph. This seems very low to me.

I am unable to get a router to associate to the coordinator through a single breeze block wall. This is a distance of 3m + wall!

I have fiddled with the power level settings on all of the modules. I thought maybe the signal strength was too high and I was saturating them but reducing power does not change things.

I have also turned off all my wifi routers and disabled the wifi adapters on the computers while doing the tests - no change.

I was expecting a lot more range out of the modules to be honest, especially as they are the pro version. I am only able to use them within the same room at the moment!

I think the seeed studio UartsBee USB interface is capable of providing more than enough current at 3.3V to drive them.

I would like to be able to communicate though at least one concrete wall as I aim to use these to monitor electricity meters situated in the core of our high rise office building. I would like to use omnidirectional antennas.

Any thoughts?

My only thought is the UFL to RPSMA cable might be cheap and degrading the signal. I bought it on taobao in china 😉 Can somebody recommend a robust UFL to RPSMA pigtail?

Would the 900/868 MHz versions be capable of easily penetrating a building core concrete wall + some?

[link to Xbee module I have](https://www.sparkfun.com/products/13170)

[link to UartSBee USB interface](http://www.seeedstudio.com/depot/UartSBee-V5-p-1752.html)

---

<div class="post-metadata">

**Author:** ![mvut](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.digi.com/mvut/32/31_2.png) [@mvut](https://forums.digi.com/u/mvut)\
**Post date:** [November 18, 2014, 2:09pm UTC](https://forums.digi.com/t/xbee-pro-2sb-xbp24-bz7uit-004-rssi-and-range-query/13935/2 "2014-11-18T14:09:47Z")

</div>

Your issue is that you are trying to penetrate through a steel reenforced concrete wall. Something that RF just simply has issues doing. What you are going to most likely need to do is to place a router on either side of the wall. Then your modules can talk to the module on that side of the wall and through the wall via the two routers.