Research On Signal Processing Technology Of Receiverin High Speed Visible Light Communication

Visible light communication is a technology of utilizing the on off change of the light emitting diode or fluorescent lamps to transmit information.Visible light communication as a new data transmission technology,makes it possible to use high-speed Internethe as long as there is light.As a new type of communication technology, optical communication used as a green low carbon technology, has the advantages of near zero loss communication and overcomes the disadvantages of electromagneticeakage, electromagnetic interference on radio communication. In addition, the spectrum is about ten thousand times larger than the radio spectrum, with greater bandwidth and faster speed.Besides the original net equipment can meet the needs, and no need to build new net facilities. Visible light communication technology makes it possible to establish anti - interference and anti - intercepted information network. Optical communication technology has important research value and wide application prospect.In the actual visible light communication, the received siginal is not ideal. There are factors that make sigmal faded in wireless channel. The first is the interference of sunlight? light and other stray light. Multipath fading also has a bad effect on the signal. In addition, the thermal noise ?contact noise and flicker noise in LED driver circuit? receiver photoelectric sensor and digital oscilloscope also interfere with the quality of the communication.In order to improve the communication quality and restrain the interference of the external interference to the signal, this paper propose some feasible improvement scheme.1. Mon Castro ray tracing algorithm is used to simulating the propagation path of each light. The channel characteristics are analysesed.2. This paper discusses the commonly used modulation in opticalcommunication, including OOK? QAM? OFDM and so on. A blind equalization algorithm for the receiving end of the visible light communication system under OFDM modulation come true. The experimental verification is completed.3. This paper design and realize visible light spread-spectrum communication experiment. Spread spectrum can effectively improve the performance of visible light communication.