SRTOMS: A Hybrid Split-Row Threshold Offset Min-Sum LDPC Decoder for Secure Low-Latency 5G-NR Communications

The rapid evolution of 5G-NR and the increasing demand for secure and low-latency communications require strong error-correction techniques that are compatible with cryptographic systems. In this paper, a hybrid LDPC decoding algorithm, Split-Row Threshold Offset Min-Sum (SRTOMS), is proposed, which embeds the offset correction of Offset Min-Sum (OMS) within the partitioned structure of Split-Row Threshold (SRT) decoding. SRTOMS is designed for 5G-NR LDPC codes and targets a trade-off between error-correction performance and hardware complexity. Under identical conditions (BG2, rate 5/8, $Z=144$, AWGN channel, and six iterations), SRTOMS reaches a BER of ${10}^{-5}$ about 1.3 dB earlier than SRT, while remaining about 1.25 dB behind OMS, and it keeps the partitioned, low-routing structure of SRT. For three encrypted images transmitted over an AWGN channel, hardware–software co-simulation shows a sharp BER drop between 3 and 4.5 dB; at 4.5 dB, one, six and zero residual bit errors remain (BER of $1.9\times {10}^{-6}$, $3.8\times {10}^{-6}$ and 0), reported with 95% confidence intervals. The FPGA implementation of the SRTOMS core requires 420 LUTs and 6 DSP slices and operates with a clock period of 2.02 ns. These results indicate the potential of SRTOMS as a candidate for secure and low-complexity 5G-NR communication.