NOMA-based Visible Light Communication System Without Equalizer

The visible light communication system can be used for communication while lighting.It has developed rapidly due to its many advantages such as no electromagnetic interference,abundant spectrum resources and green environmental protection.However,in traditional visible light communication systems,pre-equalizer is often used to increase the modulation bandwidth of LED,and post-equalizer is used to solve the problem of inter-symbol interference caused by the multipath effect of the channel.But when the equalizer is working,it will consume a lot of energy of the signal,so,we propose a visible light non-equalization communication system based on NOMA technology.Firstly,the basic principle and research background of traditional visible light equalization communication system are introduced in this paper.The problem of equalizer energy loss is analyzed from theory and simulation.Simulation analysis shows that the equalizer will consume about 90% of the energy of the signal.In order to solve the problem of energy loss,we propose a visible light non-equalization communication system based on NOMA technology.Secondly,we introduce this communication system.It mainly introduces from the transmitter,receiver,power allocation algorithm and serial interference cancellation technology of the system..Finally,we simulate and analyze the non equalization communication system.It is mainly for the dual-user situation where the transmitter uses a fixed power allocation algorithm to allocate power to it,and the receiver uses serial interference cancellation technology to demodulate these two users.By analyzing the bit error rate of these two users separately,it is concluded that both users can meet the minimum standard of communication error rate and can receive demodulation successfully.This verifies the feasibility of using NOMA technology to replace the equalizer in the traditional communication system,i.e.,the non-equalization communication system.