# A Two-staged Adaptive Successive Cancellation List Decoding for Polar Codes

## TL;DR

This paper introduces a two-staged adaptive SCL decoding algorithm for polar codes that maintains a constant data rate and significantly improves throughput with minimal performance loss, suitable for hardware implementation.

## Contribution

A novel hardware-friendly two-staged adaptive SCL decoding method for polar codes that supports constant data rate and enhances throughput.

## Key findings

- Throughput is tripled under good channel conditions.
- Decoding performance degradation is negligible.
- Hardware overhead remains minimal.

## Abstract

Polar codes achieve outstanding error correction performance when using successive cancellation list (SCL) decoding with cyclic redundancy check. A larger list size brings better decoding performance and is essential for practical applications such as 5G communication networks. However, the decoding speed of SCL decreases with increased list size. Adaptive SCL (ASCL) decoding can greatly enhance the decoding speed, but the decoding latency for each codeword is different so A-SCL is not a good choice for hardware-based applications. In this paper, a hardware-friendly two-staged adaptive SCL (TA-SCL) decoding algorithm is proposed such that a constant input data rate is supported even if the list size for each codeword is different. A mathematical model based on Markov chain is derived to explore the bounds of its decoding performance. Simulation results show that the throughput of TA-SCL is tripled for good channel conditions with negligible performance degradation and hardware overhead.