面向 OCC 系统的 QC-LDPC 编译码算法设计与实现

Design and Implementation of QC-LDPC Encoding and Decoding Algorithm for OCC Systems

摘要

针对可见光信道中的干扰较强, 且现阶段 OCC(Optical Camera Communication)系统的编码技术纠错性能不足, 造成 OCC 系统可靠性降低的问题, 提出了一种面向 OCC 系统的 QC-LDPC(Quasi-Cyclic Low Density Parity Check Code)编译码算法。根据 OCC 系统的结构特点以及信道链路特性, 确定具有结构化设计和低复杂度译码特性的 QC-LDPC 码作为纠错码型, 采用快速编码算法减小编码过程的运算复杂度; 结合归一化最小和算法和分层译码算法的各自特点提出了一种改进的 L-MS(Layer-Min Sum)译码算法。OCC 系统实验平台测试结果表明, 在室内环境通信场景下, OCC 系统的误码率为3.16×10^-6, 通信速率为2 850.4 bit/s; 在室外环境通信场景下, OCC 系统的误码率为9.07×10^-6, 通信速率为2 797.9 bit/s, 在保证低误码率的同时, 兼顾了数据的传输速率。

Abstract

The strong interference in the visible channel and the insufficient error correction performance of the coding techniques for OCC(Optical Camera Communication) systems cause the reliability of OCC systems to be reduced. A QC-LDPC(Quasi-Cyclic Low Density Parity Check Code) compilation code algorithm for OCC system is proposed. According to the structural characteristics of OCC system and channel link characteristics, QC-LDPC code with structured design and low-complexity decoding characteristics is identified as the error correction code type, and fast coding algorithm is used to reduce the computational complexity of the coding process. Combined with the normalized least-sum algorithm and the layered decoding algorithm, an improved L-MS(Layer-Min Sum) decoding algorithm is proposed. The experimental results show that the BER(Bit Error Rate) of the OCC is 3.16×10 ^-6. The communication rate is 2 850.4 bit/s under the communication scenario of indoor environment. The BER of the OCC system is 9.07×10 ^-6 and the communication rate is 2 797.9 bit/s under the communication scenario of outdoor environment. The proposed method effectively maintains a low bit error rate while ensuring a satisfactory data transmission rate.

关键词

可见光相机通信 / 编译码 / LDPC 码 / 现场可编程门阵列 / 帧结构

Key words

optical camera communication / encoding and decoding / quasi-cyclic low density parity check code(LDPC)code / field-programmable gate array(FPGA) / frame structure

参考文献

[1] LIU W, XU Z. Some Practical Constraints and Solutions for Optical Camera Communication[J]. Philosophical Transactions of the Royal Society A, 2020, 378(2169): 1-25.

[2] UTAMA I B K Y, SITANGGANG O S, NASUTION M R A, et al. Enhancing Optical Camera Communication Performance for Collaborative Communication Using Positioning Information[J]. IEEE Access, 2024, 12: 11795-11809.

[3] ZADOBRISCHI E. The Concept Regarding Vehicular Communications Based on Visible Light Communication and the IoT [J/OL]. Electronics, 2023, 12: 1359 [2025-06-01]. https://webofscience.clarivate.cn/wos/alldb/full-record/WOS:001151713300001.

[4] LIU A, SHI W, OUYANG M, et al. Characterization of Optical Camera Communication Based on a Comprehensive System Model[J]. IEEE Journal of Lightwave Technology, 2022, 40(18): 6087-6100.

[5] HASAN M K, ALI M O, RAHMAN M H, et al. Optical Camera Communication in Vehicular Applications: A Review[J]. IEEE Transactions on Intelligent Transportation Systems, 2021, 23(7): 6260-6281.

[6] NGUYEN H, UTAMA I B K Y, JANG Y M. Enabling Technologies and New Challenges in IEEE 802.15.7 Optical Camera Communications Standard[J]. IEEE Communications Magazine, 2023, 62(3): 90-95.

[7] SAXENA V N, GUPTA J, DWIVEDI V K. Secured End-to-End FSO-VLC-Based IoT Network with Randomly Positioned VLC: Known and Unknown CSI[J]. IEEE Internet of Things Journal, 2022, 10(2): 1347-1357.

[8] TAMANG L D, KIM B W. Optical Camera Communication for Vehicular Applications: A Survey[J]. IEIE Transactions on Smart Processing & Computing, 2021, 10(2): 136-145.

[9] CHENG L, WU Y, XU C, et al. Automotive Visible-Light Communication: Alternative Devices and Systems[J]. Tsinghua Science and Technology, 2023, 28(4): 719-728.

[10] 于浩海. 可见光相机通信系统发射机优化与解码算法研究[D]. 长春: 吉林大学, 2024.

[11] YU H H. Research on Transmitter Optimization and Decoding Algorithm for Optical Camera Communication System[D]. Changchun: Jilin University, 2024.

[12] 闫晓明, 韩倩倩, 籍风磊. 基于遮挡重检测的 OCC 系统目标 LED 阵列跟踪算法[J]. 实验技术与管理, 2024, 41(11): 8-15.

[13] YAN X M, HAN Q Q, JI F L. Investigation of Target LED Array Tracking Algorithm in the Optical Camera Communication System Based on Occlusion Redetection[J]. Experimental Technology and Management, 2024, 41(11): 8-15.

[14] ZHANG P, LIU Z, HU X, et al. Constraints and Recent Solutions of Optical Camera Communication for Practical Applications [J/OL]. Photonics, 2023, 10(6): 608 [2025-06-01]. https://webofscience.clarivate.cn/wos/alldb/full-record/WOS:001015530000001.

[15] HASAN M K, CHOWDHURY M Z, SHAHJALAL M, et al. Performance Analysis and Improvement of Optical Camera Communication [J/OL]. Applied Sciences, 2018, 8(12): 2527 [2025-06-01]. https://webofscience.clarivate.cn/wos/alldb/full-record/WOS:000455145000195.

[16] LIN D, YI F, YONGLIANG G, et al. Design of Protograph LDPC-Coded MIMO-VLC Systems with Generalized Spatial Modulation[J]. China Communications, 2024, 21(3): 118-136.

[17] BOCHAROVA I E, KUDRYASHOV B D, OVSYANNIKOV E P, et al. Optimization of Irregular NB QC-LDPC Block Codes over Small Alphabets[C]// IEEE Information Theory Workshop (ITW), Virtual Event. [S.l.]: IEEE, 2021: 1-5.

[18] CUMMINS A D, MITCHELL D G M, PERRINS E. Rate-Compatible, Bandwidth-Efficient LDPC Codes for Aeronautical Telemetry [J/OL]. Entropy, 2024, 26: 1045 [2025-06-01]. https://webofscience.clarivate.cn/wos/alldb/full-record/WOS:001387688500001.

[19] HOCEVAR D E. A Reduced Complexity Decoder Architecture via Layered Decoding of LDPC Codes[C]// IEEE Workshop on Signal Processing Systems. Austin, Texas, USA: IEEE, 2004: 107-112.

[20] CHOUDHARY J, CHOUDHARY A. Enhancement in Morphological Mean Filter for Image Denoising Using Glcm Algorithm[J]. International Journal of Computer Theory and Engineering, 2021, 13(4): 134-137.

[21] CHLIVEROS G, TZANETATOS I, KONTOMARIS V S. A Deep Learning Image Corrosion Classification Method for Marine Vessels Using an Eigen Tree Hierarchy Module[J]. Coatings, 2024, 14(6): 768-768.

基金资助

吉林省科技发展计划重点研发基金资助项目(20200401122GX)

吉林大学实验技术重点基金资助项目(SYXM2024a009)