Research On Error Correction Coding In Satellite Navigation System

Satellite navigation and positioning have gradually become an essential part of contemporary people's life.As a basis for positioning,the accuracy of navigation message transmission directly affects the positioning accuracy.The introduction of appropriate channel coding methods in navigation message design can effectively improve the reliability of information transmission.In recent years,with the development of computer technology and satellite navigation systems,and people's increasing requirements for navigation and positioning accuracy,many channel coding methods used in the traditional communication field have been gradually used in the design of satellite navigation message.Due to the limitation of force majeure factors such as transmit power,channel capacity,received SNR,etc.adopting superior error correction coding methods have become an inevitable trend in the navigation message design of future satellite navigation systems.Aiming at the need for the new generation navigation message design of global satellite navigation system,the following studies have been conducted in this paper:1.The structure of the global satellite navigation system,positioning principles and the content and role of the navigation message are analyzed.Through studying the open interface files of Beidou system,Galileo system,GLONASS system and GPS system,structures of navigation message and error correction coding methods for these satellite navigation systems are analyzed.2.For the error correction coding methods of the aforementioned four satellite navigation systems,the convolutional code,BCH code,low-density parity check code,Hamming code,cyclic redundancy check code encoding and decoding methods are studied.Further,the encoding and decoding methods of Turbo code and different interleavers are studied.3.Performance simulations of the error correction encoding method in the navigation message are performed using channel modeling,and the performance of each error correction codes are compared under different parameters.Based on the theoretical research and simulation results and combined with the characteristics of navigation messages,the selection of parameters for different encoding and decoding methods in the navigation message error correction coding are proposed.4.The performance differences and characteristics of different error correction codes are comprehensively analyzed and compared.Combining with the characteristics and data types of the navigation message,a design scheme for the navigation message error correction coding for satellite navigation system is proposed for the design requirements of message frame length,code rate,transmission efficiency,and transmission reliability.