Research And Analysis Of Channel Coding Technology In VDE-TER Multi-Link Mode

The very-high-frequency(VHF)data exchange system(VDES)is a new method of maritime digital communication system proposed under the development background of the e-navigation strategy and intelligent internet of ship.Among them,high performance coding technology is a key scientific problem to efficiently and reliably transmit data through VDES.For this,this paper focused on the channel coding technology under different link configuration modes of VDE-terrestrial(VDE-TER)channel.This research is of great significance to the improvement of VDES communication performance and the formulation of VDES international standards.According to the characteristics of the VDE-TER channel,this paper designed a VDE-TER channel configuration model,and on this basis,designed a theoretical coding model of low-density parity-check(LDPC)coding technology for VDE-TER channels.This coding model uses the link configuration ID to determine the number of rows and columns of the parity-check matrix of the LDPC code to control the code rate and data length required for different links of the VDE-TER channel.Based on the performance simulation analysis of different decoding algorithms,the optimal decoding algorithm and decoding factor of LDPC code in VDE-TER channel were studied.The results show that compared with other algorithms,the normalized min-sum(NMS)algorithm has the best comprehensive decoding performance for the VDE-TER channel LDPC coding scheme.When the normalization factor is 0.8 and the maximum number of iterations is 15 in the NMS algorithm,the VDE-TER communication performance is maximized.This paper further studied and analyzed the puncturing mechanism,optimal decoding algorithm and decoding factor of Polar codes in VDE-TER channel.The results show that,compared with other puncturing mechanisms,the improved random puncturing mechanism has the best performance for VDE-TER channel Polar codes;when the decoding algorithm adopts the cyclic redundancy check assistant successive cancellation list(CA-SCL)algorithm with search width of 32,the communication performance of VDE-TER is the best.Based on the above research,combined with the relevant knowledge of radio communication,this paper built a VDE-TER communication simulation system.On this system,the performance of Turbo code,LDPC code,and Polar code under 9 link configuration modes of VDE-TER channel was studied and analyzed,and the channel coding technology scheme under VDE-TER multi-link mode was proposed.The results show that:under the 11 link configuration mode,the performance of VDE-TER communication using Polar code as channel coding technology is better;under the 12,13,15,16,18 and 19 link configuration mode,the performance of VDE-TER communication using LDPC code as channel coding technology is better;under the 14 and 17 link configuration mode,the performance of VDE-TER communication using Turbo code as channel coding technology is better.This research can provide a theoretical basis for the subsequent revision of VDES technical characteristics,and is of great significance to improve the communication performance of VDES and its engineering implementation.