Hi,
Actually I test the transceivers CC2500, CC2420 and CC1100 to find the best transceiver for my application.
On all these transceivers I have seen RSSI variations (RSSI register value) in the ranges of 0 - 8dBm, with fixed transceiver positions and burst transactions.
I use the option "APPEND STATUS", so the RSSI value and the LQI value are added to the paket. Actually I don´t know, what´s the reason for these variations.
In the TI-documentation I have found the DN505 - "RSSI Interpretation and Timing" - where the RSSI Response Time is described. Knowing this fact, I have readout the RSSI registers several times after a paket received, with time spaces of 300us - no changes - always the same register value.
Now I have some question, I´ll ask:
1) Which RSSI-variations are "normal", respectively which variations have other people measured (comparative values)?
2) If I have activate "APPEND STATUS", does the transceiver logic consider the RSSI Response Time, descriped in DN505?
Can anybody help me on this topic.?
germue
Hello Germue,
I believe what you are seeing is at least in part an artifact of the error in the RSSI values. This can be up to something like 6dB in itself.
I hope this helps explain what you are seeing.
Cheers,
Yoda