Hi,
The SNR level received by the RAK5146 module is very bad.
I fixed two LoRa gateways on the roof of my company to compare the reception levels.
An industrial gateway of the Kerlink brand and a home gateway builded with a RAK5146 PiHAT kit and a Rock Pi 4C+ processor card.
Two SEMTECH packet forwarders run with the same configurations on the 2 gateways.
The 2 gateways are equipped with an ISM 868M 6 dBi antenna.
A LoRa sensor placed on my desk emits a LoRa frame in SF12 BW125.
Below are the reception levels of the 2 packet forwarders.
/* Logs Packet Forwarder GTW Kerlink */
[root@Wirnet_08050084 pf]# ./GWFw_pkt_AE | grep 867.00
JSON up: {“rxpk”:[{“tmst”:36699996,“chan”:5,“rfch”:0,“freq”:867.000000,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“lsnr”:6.2,“rssi”:-97,“size”:20,“data”:“AgAAaAgU7wyt4rTncQKvqUAMfCc=”}]}
JSON up: {“rxpk”:[{“tmst”:41775708,“chan”:5,“rfch”:0,“freq”:867.000000,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“lsnr”:6.5,“rssi”:-97,“size”:20,“data”:“AgAAaAgV7wwQ+kTJ8969RHgLr00=”}]}
JSON up: {“rxpk”:[{“tmst”:46168804,“chan”:5,“rfch”:0,“freq”:867.000000,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“lsnr”:6.0,“rssi”:-97,“size”:20,“data”:“AgAAaAgW7wzEQ5uo5nRiMIL+Qyc=”}]}
JSON up: {“rxpk”:[{“tmst”:50531436,“chan”:5,“rfch”:0,“freq”:867.000000,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“lsnr”:5.5,“rssi”:-97,“size”:20,“data”:“AgAAaAgX7wyGMYJg6FVNsL8KMIQ=”}]}
JSON up: {“rxpk”:[{“tmst”:54867740,“chan”:5,“rfch”:0,“freq”:867.000000,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“lsnr”:5.5,“rssi”:-97,“size”:20,“data”:“AgAAaAgY7wwLUYymuNJhz9uLnYI=”}]}
JSON up: {“rxpk”:[{“tmst”:59315924,“chan”:5,“rfch”:0,“freq”:867.000000,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“lsnr”:5.2,“rssi”:-96,“size”:20,“data”:“AgAAaAgZ7wx9feGJ+qGRuXeOSqY=”}]}
/* Logs Packet Forwarder GTW RAK5146 */
root@rock-4c-plus:/opt/eu868_pf# ./eu868_tcp_pkt_fwd | grep 867.00
INFO: radio 0 enabled (type SX1250), center frequency 867000000, RSSI offset -215.399994, tx enabled 1, single input mode 0
JSON up: {“rxpk”:[{“jver”:1,“tmst”:5440881,“chan”:5,“rfch”:0,“freq”:867.000000,“mid”: 0,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“rssis”:-92,“lsnr”:-3.5,“foff”:516,“rssi”:-89,“size”:20,“data”:“AgAAaAgU7wyt4rTncQKvqUAMfCc=”}]}
JSON up: {“rxpk”:[{“jver”:1,“tmst”:10516599,“chan”:5,“rfch”:0,“freq”:867.000000,“mid”: 0,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“rssis”:-94,“lsnr”:-2.8,“foff”:518,“rssi”:-91,“size”:20,“data”:“AgAAaAgV7wwQ+kTJ8969RHgLr00=”}]}
JSON up: {“rxpk”:[{“jver”:1,“tmst”:14909699,“chan”:5,“rfch”:0,“freq”:867.000000,“mid”: 1,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“rssis”:-96,“lsnr”:-5.0,“foff”:519,“rssi”:-91,“size”:20,“data”:“AgAAaAgW7wzEQ5uo5nRiMIL+Qyc=”}]}
JSON up: {“rxpk”:[{“jver”:1,“tmst”:19272331,“chan”:5,“rfch”:0,“freq”:867.000000,“mid”: 0,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“rssis”:-95,“lsnr”:-4.8,“foff”:519,“rssi”:-91,“size”:20,“data”:“AgAAaAgX7wyGMYJg6FVNsL8KMIQ=”}]}
JSON up: {“rxpk”:[{“jver”:1,“tmst”:23608638,“chan”:5,“rfch”:0,“freq”:867.000000,“mid”: 1,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“rssis”:-96,“lsnr”:-6.0,“foff”:519,“rssi”:-91,“size”:20,“data”:“AgAAaAgY7wwLUYymuNJhz9uLnYI=”}]}
JSON up: {“rxpk”:[{“jver”:1,“tmst”:28056828,“chan”:5,“rfch”:0,“freq”:867.000000,“mid”: 0,“stat”:1,“modu”:“LORA”,“datr”:“SF12BW125”,“codr”:“4/5”,“rssis”:-95,“lsnr”:-4.2,“foff”:521,“rssi”:-91,“size”:20,“data”:“AgAAaAgZ7wx9feGJ+qGRuXeOSqY=”}]}
The RAK5146 SNR level are negative !
Why ?
