调频信号的数字化解调

介绍一种用3参数正弦波拟合算法实现的、绝对收敛的4参数最小二乘正弦波拟合算法，给出了其收敛区间、绝对收敛判据以及实现过程，在此基础上讨论实现正弦载波的调频信号的精确解调问题，使用一个周期的正弦波曲线模型的滑动拟合法，实现了频率调制信号波形的精确解调，在调制信号是方波的情况下，给出了频率解调的仿真结果和其它参数的波动情况；在1个实测调频曲线波形上进行的解调分析，给出了频率调制波形的解调结果，同时，在调制信号也是正弦波的情况下，给出了解调失真的计算方法和结果。本方法是评价载波为正弦波的调频信号的一种优良方法，准确度高、分辨力强，可用于调频信号源及其解调设备的指标评价和计量测试。

A Precise Digitizing Demodulation Method of the FM Signal

A four-parameter sine wave curve-fit method is introduced, which based on the three-parameter sine wave curve-fit method, and it's an absolute convergent courses. The absolute convergent interval, the absolute convergence criterion and the actualization course are presented. Then, the demodulation of FM (Frequency Modulation) signal of function generator are discussed and achieved. By using moving one period sine wave model, the precise demodulation of FM signal wave is achieved. In the situation of modulating signal is square wave, the result of demodulation frequency is presented in imitation, and other parameter's jitter in this situation is also described. At the same time, one groups of demodulation analysis at an experimental result are given out, the definite and clear demodulation results are attained. The measuring method above is excellent in demodulating the FM signal of function generators, it can be get high accuracy, high resolution, and it can be applied to measuring and calibration both FM signal generator and its demodulation devices.