Lora-net
Implementation of SX1261-2 Limitation in DS_SX1261-2_V1.1 is not according to description
DS_SX1261-2_V1.1, chapter 15.1 describes a known limitation with modulation quality when using 500kHz LoRa bandwidth. Chapter 15.1.2 describes a workaround that is implemented here: https://github.com/Lora-net/LoRaMac-node/blob/fe8247e2b84101fe701531a5f9ef14f035743af4/src/radio/sx126x/radio.c#L854
This workaround does not match the description of the limitation: description: "The following pseudo-code can be used before each packet transmission, to properly configure the chip:"
whereas RadioSetTxConfig() is not called before each transmission, rather only once at startup.
Either the data sheet is incorrectly worded, or the implementation needs revision.
Indeed, we are also seeing this sensitivity errata continue when this is only set at startup with a ~6dBm variation between 250kHz & 500kHz.
We've validated the solution is to set this for each tx event which brings 500kHz to the expected ~3dBm difference to 250kHz.
From the datasheet:
Sorry for the late comment on this issue.
If I am not mistaken the stack always call RadioSetTxConfig prior to setting the radio in Tx mode. Thus, we think that before every uplink the workaround is applied.
Can you please indicate a situation where this is not the case?
