Device and method for downlink gain compensation as well as radio unit comprising the device

A device for use in a radio unit (RU), the device comprising:

• a pre-distortion circuit configured to generate and apply a pre-distortion to an input signal;
• a digital gain adjuster (GA), configured to apply an adjustable gain to an output signal from the pre-distortion circuit;
• a device controller comprising a processor and a memory, the memory containing instructions executable by the processor, whereby the device controller is operative to:
• determine a gain difference between a target downlink gain and current downlink gain;
• and
• control the digital GA based on the gain difference wherein the RU comprises an analog GA configured to apply an adjustable gain to an output from the digital GA and a second gain controller configured to perform a preliminary gain adjustment via the analog GA and then trigger the gain determiner to determine the gain difference.