We did a quick range test of our new CC1120 radio based sensor nodes. We did this within Pruksa (community in east Bangalore). This was a non line of sight test in which one WSN1120L node was configured to send packets to a coordinator node (a WSN1120CL) once every second. The nodes were around 526 meters apart with lots of houses in between. The nodes were at a height of around 5 feet above ground. The walls in these houses are fully concrete (no bricks). Even at this distance the signal strength was pretty good (around -75 dBm). The nodes were configured to transmit at +14 dBm at a data rate of 1.2 kbps (GFSK modulation) with channel bandwidth configured to 25 kHz.
We tried to do a line of sight test along a nearby highway but we could not find a flat stretch longer than 1.1 kilometers close by. The two nodes were able to communicate up to a distance of 1.1 kilometers. The signal strength was again very good (around -80 dBm). We will be doing further tests to find out the max range under line of sight and non line of sight conditions.
Here is a pic of one of the nodes used in the range test. The node was powered by two AA batteries.
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