On the performance of polar codes for 5G eMBB control channel

Abstract

Polar codes are a class of error-correcting codes which can provably achieve the capacity of a binary memoryless symmetric channel with low-complexity encoding and decoding algorithms. They have been selected for use in the next generation of wireless communications, as a coding scheme for the enhanced mobile broadband (eMBB) control channel, which requires codes with short lengths and low rates. Successive-cancellation (SC), SC list (SCL), and their modifications, are some of the most studied polar code decoding algorithms. In this paper, we study polar codes of short lengths and different code rates. We show that for a fixed target frame error rate (FER), there is an optimal code rate with which SC and SCL decoders can achieve it with maximum power efficiency. In addition, we study the effect of CRC on the error-correction performance of SCL decoders and show that there is an optimal CRC length with which the decoder achieves its best results. We further analyze the speed of polar code decoding by considering state-of-the-art fast SCL decoders available in literature, thus providing a survey of the decoder design space for eMBB, considering error-correction performance, achievable throughput, flexibility and estimated complexity.