A Practical Method for Power Saving in 4G, 5G, and Beyond 5G Channel Decoders Using RBIR

With sustainability as one of the key requirements and the design principles of the sixth generation (6 G) communications, implementation based power saving solutions that benefit both base station (BS) and user equipment (UE) sides have gained significant interest in the cellular industry research. Channel decoding is one of the receiver modules that can help reduce the power consumption of the receiver significantly, and is applicable to both BS and UE. In this paper, we propose a universal list size and iteration number predictor (ULIP), for reducing the power consumption, applicable for 4G, 5G and beyond-5G channel decoders. We propose to use a link abstraction abstraction metric called received bit information rate (RBIR), that captures the time-varying channel conditions to identify and choose the iteration and list sizes for these decoders, to reduce the power consumption. We evaluate the proposed ULIP for regulating the iteration number in turbo and low-density parity-check (LDPC) decoders, used in 4 G and 5 G data channels, respectively, and the list size in polar decoder, used in 5 G control channel. We also verify the proposed ULIP for regulating the list size in the recently introduced polarization-adjusted convolutional (PAC) decoder, a prospective scheme for 6 G. We show that the proposed solution has upto 54.7 % and 67.4 % reduction of iteration numbers in LDPC and turbo decoders, respectively, for a target block error rate (BLER) of 10 %, and upto $\sim 92 \%$ reduction of list sizes in both polar and PAC decoders, for a target BLER of 0.1 %, compared to conventional decoding methods.