  In this paper, we test the performance of some modern stochastic optimization
methods and practices in application to digital pre-distortion problem, that is
a valuable part of processing signal on base stations providing wireless
communication. In first part of our study, we focus on search of the best
performing method and its proper modifications. In the second part, we proposed
the new, quasi-online, testing framework that allows us to fit our modelling
results with the behaviour of real-life DPD prototype, retested some selected
of practices considered in previous section and approved the advantages of the
method occured to be the best in real-life conditions. For the used model,
maximum achieved improvement in depth was 7% in standard regime and 5% in
online one (metric itself is of logarithmic scale). We also achieved a halving
of the working time preserving 3% and 6% improvement in depth for the standard
and online regime, correspondingly. All comparisons are made to the Adam
method, which was highlighted as the best stochastic method for DPD problem in
paper [Pasechnyuk et al., 2021], and to the Adamax method, that is the best in
the proposed online regime.
