Research On Relay Transmission Method Based On Index Coding

With the development of the wireless communication technology,more and more users achieve a multimedia,Internet and other diverse information services through wireless network.The waste of wireless resources and the unreliability of wireless transmission of the wireless communication system have brought a lot of adverse effects,so how to improve the utilization of wireless resources and the reliability rate of wireless communications has become an important issue in the field of wireless communications research.To improve the effectiveness and the reliability of the system,this paper researches the relay transmission method based on the index code technology.First,in order to ensure the reliability of transmission,this paper proposes to the error correction coding for the index coded signals when the index coding technique is applied to the wireless transmission channel with noise and interference.Each coded signal is divided into multiple data packets,the influence of noise and interference is effectively reduced by adding redundant bits and redundant packets between the intra-packet and the inter-packet.This scheme can reduce the number of data transmission,but also ensure data transmission reliability.The index coded signal which is error correction coded has a low packet error rate(PER)by the simulation.In this paper,the influence of the interference probability and the total number of bits on the performance of the system is compared,and the transmission performance of different error correction codes is analyzed.What is more,this paper also compares the influence of the allocation of the redundant bits on the transmission performance of the system.Secondly,the index coding technique is applied to K-user MIMO Y transmission channel in the MIMO multi-directional relay transmission model based on side information learning.Different from the traditional signal space alignment technique,this scheme precoding vector by the index coded signal,so that the multiple independent signals in the same coded signal are aligned to the same spatial dimension to jointly perform detection and code for network code at the relay.The valid side information,the normalized degree of freedom and the side information optimal criterion are defined.By adding the valid side information to each user,we can reduce the minimum rank of the index code matrix and the number of signals transmission.Therefore,the number of antennas required of the system is reduced,and the normalized degree of freedom of the system is improved.Finally,this paper compares the coded length and the number of the antenna between the index coded scheme and the traditional signal space alignment scheme at the case of optimal side information.It is found that the proposed scheme can effectively utilize the side information and improve the transmission efficiency.What is more,this paper also analyzes the normalized degrees of freedom of the proposed scheme,signal space alignment scheme and the time scheduling scheme on the MIMO Y transmission model,the proposed scheme has the best system performance.Therefore,the index coding technology combined with other technologies can effectively improve the overall performance of the system.