Da_Stier, a user from www.highvoltageforum.net has reverse engineered the power amplifier module and this is the documentation and test results.
The RF power amplifier teardown can be seen in part 1: https://kaizerpowerelectronics.dk/teardown/nokia-siemens-flexi-3x70w-fxea-1800mhz-base-station-teardown-power-amplifier-part-1-of-2/