基于CFG的连续TTD系统研究

Continous TTD system based on CFG

提出并实验验证了一个四通道的基于啁啾光栅的连续可调光控延时系统,该系统适合于频率达10GHz的相控阵天线的波束形成及扫描,使用一种基于啁啾光栅的延时网络和一种新型的波长等间隔增大或减小的多波长可调谐线性腔光纤激光器。光纤激光器的等波长间隔,通过相等增量的作用力挤压或拉伸激光谐振器中固定在一个有机塑料盘上成一定的角度相邻的布拉格光栅来调谐。光控延时是通过被调制光在一个线性啁啾光栅的不同位置反射而实现,波长等间隔激光可获得等间隔的延时。

A four-channel chirped-grating-based continuously tunable differential true-time- delay gradient system suitable for continuous beam steering at microwave frequencies up to 10 GHz was constructed and presented here.The lasing wavelengths were determined by discrete fiber Bragg gratings in the laser cavity and can be tuned by compressing or extending the gratings. To ensure that the wavelength tuning occurs with equal wavelength spacing, the discrete gratings were mounted onto an organic plastic plate with angles between adjacent gratings such that the tuning accurs forces applied to the gratings experience equal increments of force.Time delays, with equally adjusted time delay differences for equally spaced wavelengths were achieved ifthe modulated lightwaves were reflected at different locations of a linearly chirped grating in the time-delay network.