Research on Packet Pilot Multiplexing and Encryption Strategy in 5G Mimo System

Aiming at the pilot pollution problem in large-scale MIMO system, a grouped pilot multiplexing strategy is proposed, which redistributes the pilot sequence. Users are divided into central user group and edge user group according to the severity of user interference in the cell, and the edge user is assigned a completely orthogonal pilot sequence; To solve the security problem of signal transmission in Massive MIMO systems, an iterative encryption algorithm based on pilot is presented. An iterative encryption module is added to the modulation part before the pilot signal is sent. The simulation results show that the proposed method can effectively suppress pilot pollution, suppress attacker stealing information, and improve system performance and security.