A New O-RAN Compression Approach for Improved Performance on Uplink Signals
Marcos Vinicius Maciel da Silva, Leonardo Ramalho, Igor Almeida, Eduardo Medeiros, Miguel Berg, Aldebaro Barreto da Rocha Klautau Junior · Journal of Communication and Information Systems · 2022
This work evaluates the O-RAN compression methods specified for in-phase and quadrature (IQ) data compression, which are applied to transport the frequency domain representation of the radio signals. The methods were evaluated in terms of computational cost and quantization-noise ratio vs IQ bit-width. It was found that the O-RAN compression algorithm with the best performance highly depends on the signal power. Thus, one of the contributions of this work is a compression method that selects the best method for each physical resource block (PRB) instead of using a single compression method for a set of PRBs as in the current O-RAN specification. A complete description of how to implement the proposed method meeting the O-RAN standard is also provided in the paper. The selection of the best method for each PRB is particularly important for the uplink signals, where the power of the received signals can be very different depending on the UE channel.