一种正弦信号发生器的设计方法

基于正弦脉宽调制（SPWM）理论，提出适合于数字电路实现的，抗干扰性强，可靠性较高的一种正弦信号发生器构想，给出了滤除3次和3的倍数次谐波的简单方法，以及5次、7次谐波的滤除方法。电路仿真表明，该信号发生器较常规的DDS方法实现的正弦信号发生器易于实现电压和频率的调整，且调试和使用成本较低。它与查表法的正弦信号发生器相 比，频率范围宽、容易调整，文中同时给出了相应的频谱分析。

Design Procedures of a Sinusoidal Signal Generator

Based on the theory of sine pulse width modulation, the author puts forward a proposition on a sinusoidal signal generator which fits to be realized by digital circuit and is powerful in noiseproof feature and is high in reliability; and gives a simple method for eliminating triplen as well as quintic and septic harmonic waves. As indicated by circuit simulation, this signal generator is easier to realize voltage and frequency regulation and is lower in cost of debug and service than the one realized by conventional DDS method; this one has a wider frequency range and is easier to be regulated as compared with the one using table lookup method. In this paper, corresponding frequency spectrum analysis is given simultaneously.