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RSSI estimation with SX1301

Hi!

I am looking forward to gather RSSI values with SX1301 based LoRaWAN gateway. In
the repository libloragw (https://github.com/Lora-net/lora_gateway/tree/master/libloragw)
inside "loragw_hal.c" there are some registers apparently connected to RSSI estimation:
lgw_reg_w(LGW_RSSI_BB_FILTER_ALPHA,6); /* default 7 */
lgw_reg_w(LGW_RSSI_DEC_FILTER_ALPHA,7); /* default 5 */
lgw_reg_w(LGW_RSSI_CHANN_FILTER_ALPHA,7); /* default 8 */
lgw_reg_w(LGW_RSSI_BB_DEFAULT_VALUE,23); /* default 32 */
lgw_reg_w(LGW_RSSI_CHANN_DEFAULT_VALUE,85); /* default 100 */
lgw_reg_w(LGW_RSSI_DEC_DEFAULT_VALUE,66); /* default 100 */

My question is: How do these values affect RSSI estimation?

My goal is to achieve RSSI estimation such that for completely static channel conditions (or even for a direct cable connection between SX1276 and SX1255&SX1301; via attenuator) the collected RSSI values from uplink LoRaWAN packets do not show significant variance.
Hello,

These values are also for the AGC settings, more ALPHA values is high, more stable the RSSI will be, BUT the AGC response time will be decreased.

I strongly advise you to DON'T change these values because you will degraded the gateway performance.

Regards,

Benjamin