针对传统液位测量系统精度低、抗干扰能力差、接触式的特点,介绍一种利用雷达原理研制的数字式液位测量系统。本系统采用调频测量法,用C8051F020单片机作为频率测量模块的核心。运用自相关函数对信号进行滤波 快速傅里叶变换(FFT)算法进行频域分析 移频法对频率进行细化,最后得到液位的高度。该系统具有很强的适应能力和完善的接口,在实测中取得了满意的精度。 -Traditional level measurement system accuracy, anti-jamming capability, contact, on a radar principle of the development of digital liquid level measurement system. The system uses the FM measurement, frequency measurement with C8051F020 MCU as the core of the module. Used the autocorrelation function of signal filtering　Fast Fourier Transform (FFT) algorithm, frequency-domain analysis　frequency shift on the frequency refinement, the final height of the level. The system has a strong ability to adapt and improve the interface, in measured with satisfactory precision.