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Is there Gain Control in LoRaTM modem?

Hello,

I am using Seeeduino LoRaWAN with GPS board (transmitting at LoRa 868.1 MHz and LoRa 868.3 MHz Europe) where I need read that the RHF76-052DM module include LoRa SX1276 Transceiver. I understood when readin the datasheet (“SX1276/77/78/79 - 137 MHz to 1020 MHz Low Power Long Range Transceiver”, Datasheet, Semtech Coporation, 2015) that Gain Control is available when using FSK Modem.

So, how is the Receiver Gain can be controlled in LoRaTM modem?

I would appreciate if someone can clarify.

Kind regards,
Mohammed

Someone from Semtech will answer you better, but I would say:
In REG_LR_MODEMCONFIG3 (0x26), set AgcAutoOn (bit 2) to 0 (0 = LNA gain set by register LnaGain) to turn off the automatic gain control (AGC).
In REG_LR_LNA (0x0C), set LnaGain (bits 7-5) to your desired (receiver) low-noise amplifier (LNA) gain. You can choose between six gain settings.
(Since you are using the HF band) Also in REG_LR_LNA (0x0C), set LnaBoostHf (bits 1-0) to 0b00 if you want the default LNA current, or to 0b11 if you want more (150%) LNA current, to have more gain / less noise.