The Research Of Transmitting Audio And Video Signals In Laser Communicaiton Technology

In recent years, wireless laser communications technology has become practical gradually,and it not only could provide similar optical fiber transmission rate, but also do not need, such as microwave communications,large initial investment in the aspects of scarce resources spectrum.Therefore,the prospect of wireless laser commu- nication must become much broader,whether in the military or commercial application.In this paper,we focus on the design and implementation of the system's transmitter according the pcinciples of wireless laser communication system,and combining the technology of wireless laser communication technology and audio and video codec technology. In this paper, input video and audio signals are processed by digital processing measure,and the main task is compression encoding processing of the audio and video signal as the source: using G.729 coding standard for audio processing,and using MPEG-4 coding standard for video processing; after that process the package deal. After Compression.modulate the digital baseband signal on FPGA as a platform, and through transform a two-way differential serial signal and transmit to lasers.There using semiconductor laser as light source,and the wavelength is 1550nm, output power is 2mW, the meaning of modulation is direct light stress modulation.FoUowed by the introduction of laser driver circuit and protective measures. Finally, the paper complete the connection of sending part and recieving part of the system, testing and debugging work,and the results of testing prove the feasibility of the design in this paper.The system could realize the transmission of audio and video signals in the condition of wireless laser communication.