用金属氧化物半导体(MOS)晶体管模型取代传统Colpitts混沌振荡电路中的三极管模型,提出了一种基于MOS管的Colpitts混沌振荡电路。通过合适的归一化方法,得到了与基于三极管电路类似的状态模型。平衡点的指标说明两种结构产生混沌的机理并不相同。然后,通过参数反演,得到了详细的电路参数,并用Pspice软件仿真得到了混沌吸引子和混沌信号的频谱图,说明了此结构可在低电压下工作并且能产生高频率的混沌信号。最后,用误差反馈的方法实现了这种结构的同步。
A Colpitts chaotic oscillator is proposed by replacing the bipolar transistor with metal oxide semiconductor (MOS) transistor. Through a series of variable transformations, a state model of proposed circuit similar to one of traditional Colpitts oscillators with bipolar transistors is established. The system parameters are easily obtained by matching the two similar models. Indexes of the balance point show that chaos mechanisms of the two structures are not the same. After the process of parameter inversion and scaling transformation, the detailed circuit parameters are determined. Chaotic attractor and chaotic signal frequency diagrams are generated on PSpice platform. The simulations show that the proposed structure can work under low voltage and can generate chaotic signal with high frequency. Finally, using the linear error feedback method, a synchronization of two identical chaotic circuits is achieved.