新型光Nyquist脉冲源研究

等效时间取样示波器从机理上决定了其只能测量周期性信号，不能观察非周期性信号和瞬态突发事件信号，而高速的实时示波器又受“电子瓶颈”限制。超越电子瓶颈的技术虽然有，但面临重重困难。本项目拟采用多段光谱资源汇接的办法扩展电谱域带宽，绕过电子瓶颈限制去获得超高速的取样脉冲。其特色是将高端微波电子技术和前沿微波光子技术有机地融合在一个系统中，在实现脉冲宽度约为10ps的光Nyquist脉冲基础上，得到一个重复频率为100GHz的光脉冲源。这样的脉冲源可为观察光信号的实时示波器提供光取样门信号；同时光Nyquist脉冲的码间干扰特性决定了它是光时分复用通信系统中的完美光源。我们的创新之处体现在利用光谱汇接技术，绕过电子瓶颈限制得到可编程控制的高重复频率的光Nyquist脉冲，再将光Nyquist脉冲正交的特性与多波长的非相干特性巧妙地结合在一起，形成重复频率为100GH的脉冲输出。

Theoretically Equivalent-Time-Sampling Oscilloscopes (ETSO) can only be used to measure the periodical signals and it can not be used to observe the non-periodical signals or is not able to capture the instantaneously happened events. However, the high speed real-time oscilloscope is not fast enough for measuring the unexpected fast signals due to the limitation of so-called electronic bottleneck effect. It is true that the electronic bottleneck can be overpassed but it is still difficult to conquer it..In this project we would like to avoid the electronic bottleneck to extend the electric bandwidth in our ultra-high-speed optical sampling system by combination of multi-section optical spectrum resources. An optical pulse source with high repetition rate of 100GHz is going to set up in which the pulses are the optical Nyquist pulses with the duration of about 10ps. To realize the optical Nyquist pulse source the advanced microwave electrical technology and the state-of-the-art microwave photonic technology has to be merged well in a whole system..The light source can be used in a real-time oscilloscope as an ultra-fast sampling gate signal for optical signal observation. And also it would be an ideal light source in the Optical-Time-Division-Multiplexing (OTDM) communication system because of its wonderful characteristics of inter-symbol-interference (ISI). .It is a creative work for us to generate the optical Nyquist pulse with low duty-cycle, high repetition rate by using a technique of combing multi-section optical spectrum components so that the electronic bottleneck is passed by successfully. Taking the advantage of the orthogonality of the optical Nyquist pulses we generated, and the non-coherent property of the multi-wavelength laser, the pulses at the repetition rate of 100GHz can be obtained. To our knowledge, the report about the similar research proposed in this proposal has not been published so far.