一种手持式电力线载波频谱分析仪的研制

设计了一种以STM32F407为主控CPU的手持式频谱分析仪,用于现场在线分析220 V电力线载波的通信信道干扰情况。设计方法为:用RC串联无源高通滤波器和一阶有源高通滤波器级联构成载波信号提取电路; 用Multisim和TINA-TI软件组合仿真硬件,验证其载波提取能力; 用STM32F407芯片采样载波信号,通过快速傅里叶变换(FFT)运算获得载波信号的频域信息,将频谱图显示在液晶屏上。实际运行结果表明:该分析仪能够提取到40～500 kHz的载波信号,测量频域较宽,能够准确快速分析多种载波通信模块的频谱信息,具有携带方便、成本低的优势。

Research and design of power line carrier spectrum analyzer based on STM32F407

The V-type artificial main power network and a signal analyzer are usually employed coordinately to check the power line carrier communication equipment. However, it is inconvenient in field tests and the analyzer is expensive. A handheld spectrum analyzer with STM32F407 CPU was designed to identify the interference of 220 V power line. The filter circuit of carrier wave was made up of a series of RC high-pass filter and one-pole active high-pass filter. The hardware was simulated by combining software of Multisim and TINA-TI, in order to verify its capacity of carrier extraction. The carrier signal was sampled by STM32F407 chip, transformed by fast Fourier transform(FFT)algorithm into the frequency spectrum and displayed on an LCD screen. Experimental results showed that this handheld spectrum analyzer could capture wideband signals from 40 kHz to 500 kHz and analyze frequency spectrum of various power line carrier modules accurately and rapidly. Comparatively, the advantages of the proposed power line carrier spectrum analyzer are portable and cheap.