CC1310: what are possible causes for extremely low RSSI between radios that are in line of sight and only a few feet away?

Zhiyong Li (FT)

Part Number: CC1310

Hi,

We deployed a network of radios based on TI-15.4 stack into a presumably quite noisy environment. The network consists of one collector radio, and 6 sensor nodes. They are about 4 ~ 10 feet away from each other and in line of sight. TX power for all radios are set a 7dBm.

So far communication between sensor nodes and the collector node seems quite reliably. But I am puzzled by the fact that RSSI as seen by both all sensor nodes and collector node are extremely low, vary between -115 and -100, average at -106 dBm. In our other similar deployments, the typical RSSI are between -70dBm and -30dBm.

What could be such low RSSI? Ideally we need to do something about it. Please advise.

Thanks,

over 2 years ago

0 Diego P over 2 years ago

TI__Expert 4860 points

For a couple of feet of separation and LOS, the RSSI is extremely low. I would expect it to be roughly around -40 to -50 dBm.

There are a couple of factors that can cause what you are seeing: poor receiver sensitivity, poor tx output power, bad antenna matching among other factors.

I recommend going through our Debugging Communication Range app note find what is causing the poor RSSI.

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CC1310: what are possible causes for extremely low RSSI between radios that are in line of sight and only a few feet away?