The Optimized Retransmission Size Choosing of RB-HARQ Implemented in Secure Communication for High Throughput

A physical-layer coding scheme is designed to enhance the efficiency on the premise of secure communication in this paper. It combines low-density parity-check (LDPC) codes with reliability-based hybrid automatic repeat-request (RB-HARQ) protocol. Specifically, the scheme adapts to the channel conditions and choose the optimized sizes of succeeding retransmissions for high throughput. Moreover, this paper employs the density evolution (DE) method to analyze the message probability density (MPD), which assists in obtaining the approximate bit-error rate (BER) in theory. With the assessment of BER and throughput, simulation results demonstrate the performance of our design.