Design And Implementation Of Transceiver For Wireless Optical Data Communication System

Wireless laser communication is a communication technology that uses laser as a carrier and atmosphere as a medium to transmit information such as data,images,audio and video,etc.Compared with optical fiber communication,it has numerous advantages that include without laying lines,flexible networking and short construction period,etc.Compared with radio communication,it has the advantages of large communication capacity,no occupation of radio spectrum resources,strong anti-jamming ability,etc.So it`s a promising communication method.At present,wireless laser communication is mainly used in military communications and other high-end fields,but it has not been widely used in comm ercial and civilian fields.Therefore,in order to speed up the popularization of wireless laser communication in commercial and civilian fields,this thesis completed the design of a transmitter and receiver for wireless laser communication system.Its ma in work is as follows:(1)In this thesis,a L650P007 red semiconductor laser is used as the light source,MAX3669 is used as the laser driver,a transmitter based on intensity modulation wireless laser data communication system is designed by internal modulation.Among them,the level matching method adopts the AC coupling connection mode of LVDS to LVPECL.The transmitter has automatic power control,fault indication,current monitoring and other functions.And it can be manually calibrated,when installing and debugging it.At the same time,it is convenient to replace laser diodes with different power and wavelength which meet the requirements of the transmitter.(2)This thesis uses S1223 Si-PIN photodiode as photodetector,MAX3658 transimpedance amplifier as preamplifier,MAX3645 limit ing amplifier as main amplifier,a receiver of wireless laser data communication system based on direct detection is designed.Among them,the level matching method adopts the AC coupling connection mode of LVPECL to LVDS.The receiver has functions such a s signal amplification,photocurrent monitoring,and automatic squelch.Finally,the overall performance of the transceiver is tested with the established experimental system.Among them,the system source uses waveform generator Tektronix AFG320,and the sink uses oscilloscope RIGOL DS1052 E.The performance of the transceiver is tested in indoor environment.The test results show that the transceiver can achieve 16 MHz transmission rate,and the signal can be reliably transmitted within a distance of 100 m.At the same time,the transceiver has the characteristics of small size,simple design,low power consumption and good stability.It has good application value in wireless laser communication system,and provides a basis for further research of wireless laser data communication system.