Construction And Simulation Test Of Multicarrier CDMA System Based On The Complementary Code

Now mobile communication systems have become an integral part of a modern life.With the evolution of the cellular system,the fourth generation cellular mobile communication has stepped into our daily lives gradually.With the face of the explosive growth of global wireless data communication services,we should continue to improve the data transmission rate,provided by a wireless communication system.But in the complicated wireless transmission environment,the reliable transmission for high rate data is the biggest challenge for all wireless communication systems.For cellular mobile communication systems,the core challenge is air interface access technology,also known as multiple access method.Wherein,CDMA technology has strong anti-interference capacity,high detection effectiveness,strong privacy,low radiation signal power,etc.So,it is favored by many researchers and communications companies.In this paper,combining the traditional CDMA features,we design a new CDMA system,which is based on the complementary code multicarrier CDMA systems,and we analyze its performance,propose an improvement method.Complementary codes for multicarrier CDMA system simulation test,and the two despreading way system was simulated.At the same time,taking into account the impact of the distance effect for the system,its distance effect simulation.This paper analyzes the auto-correlation and cross-correlation properties of the complementary code,and its performance in multiuser and frequencyselective channel.By the theoretical analysis and simulation,the comparison with the traditional spreading codes is given out.Theoretical analysis and simulation results show that,under the same spreading gain and channelconditions,the complementary code multicarrier CDMA system has better error rate performance.This Complementary code-based multicarrier CDMA system is not only inherits the advantages of traditional CDMA,it also overcome the poor correlation property of traditional spreading code,which will lead to multiuser interference.We also proposes an adaptive combination plan,so a more reasonable choice between diversity gain and perfect orthogonal can be made to achieve the best system performance.