Millimeter Wave Generation Methods Based On External Intensity Modulator

With the development of multimedia technology,network access content from the audio signal is expanded to the data transmission and video playback,therefore,the capacity bottleneck of transmission of video signal and data wireless communication technology has become the urgent problem to solve.Is currently in use and the technology is relatively mature 3G mobile communication system adopts cellular system capacity,transmission speed can reach 2Mbps,and achieve seamless coverage and has larger capacity.But has gradually began to provide 4G service speed can reach 100Mbps,the number of users than 3G system is an order of magnitude higher,in this case 4G wireless access will need to reconstruct the traditional cellular system,or the use of more advanced program,to make up for use from the traditional cellular structure capacity,speed and coverage rate lack of requirements.Optical wireless communication technique to large capacity transmission of optical fiber communication and wireless access flexibility advantages of combining,occupies an important position in the future broadband wireless access network.In optical wireless communication,the generation of millimeter wave is the key problem needed to be solved.This paper studied the different schemes to generate optical millimeter wave signal based on external modulator,as well as the influence of dispersion of the optical millimeter wave signal transmission in optical fiber process.Theoretical analysis of the effect of dispersion on optical wireless communication system,and to study the optimization design system.The main research and design of a kind of simple and effective allocation of full duplex radio over fiber(ROF)communication system.The research and design of full duplex optical wireless(ROF)communication system,mainly uses the best modulation phase modulation(PM)with bilateral generated optical millimeter wave signals,this scheme to generate optical millimeter wave signals can effectively overcome the fiber dispersion effects,and is not affected by the bias effect,can effectively reduce baseband signal the signal delay of fiber dispersion caused by degeneration.Similar to double sideband suppressed carrier way,namely filtering bilateral with carrier optical millimeter wave.This scheme using only one sideband modulated data signal,not only to improve the downlink signal anti noise capability,reduce power cost,can also save a laser source base station uplink,which simplifies the base structure,but also reduce the cost of the system.ignal modulation can effectively overcome the influence of fiber dispersion.