| In the fields of military and communication,high-quality microwave signal source has played an important role.Traditional electronics are subject to the electronic bottleneck and can not generate and process the high-speed signal.Optoelectronic oscillator is a new type of signal generator which can produce high frequency and low phase noise microwave millimeter wave signal.Optoelectronic oscillator,which has both light and electricity output,is a very ideal microwave signal.In this thesis,the basic principle of a classical single-loop optoelectronic oscillator is introduced firstly.The parameters such as the initial conditions,the response function,the frequency and the amplitude of the optoelectronic oscillator are deduced.The frequency spectral and the noise characteristics of the optoelectronic oscillator are analyzed.The main problems and their solutions in practical application of the optoelectronic oscillator are illustrated.In order to solve the instability of the optoelectronic oscillator,a feedback control system should to be used to compensate the frequency drift of the optoelectronic oscillator.In this paper,various feedback control programs are compared and studied on the adjustment range,the impact on the system,the influence of the external environment factors,the complexity of the system and the cost of the controller and the controlled object using theoretical and experimental methods.In order to solve the problems in the error detection scheme of traditional feedback control system,two novel error detection methods are proposed in the paper.The principle of two methods is analyzed,and the optoelectronic oscillator system with a feedback control loop is established.The experimental results show that both schemes can improve the stability of the optoelectronic oscillator.These schemes which can be applied to the tunable optoelectronic oscillator can avoid the use of external reference sources.Finally,a control system circuit was designed and a prototype was made. |
PDF Full Text Request