Signal Distortion Analyzer Based on C2000

Abstract:
In the measurement and test of modern wireless communication, the accuracy of many parameters involves the problem of distortion measurement, especially in the process of signal generation, transmission and reception, the signal distortion must be measured and analyzed accurately. Signal distortion analyzer is a special instrument for measuring distortion, which is widely used in the production and detection of electronic products. This paper introduces a new signal distortion analyzer based on harmonic analysis method. The system consists of signal conditioning circuit, signal processing core board, display control panel and mobile APP(Application) display. The signal processing MCU1(Microcontroller Unit) and display control MCU2 all use C2000 series. The system takes the periodic signal with harmonic component from the signal source as the input signal, amplifies the amplitude and level of the signal conditioning circuit, and turns it into a signal matching analog-to-digital conversion ability of MCU1. Quantitative sampling using in-chip ADC(Analog to Digital Converter), FFT(Fast Fourier Transform) operation and periodic scan of MCU1, based on peak detection and windowed interpolation algorithm, achieves amplitude-frequency detection in non-integer cycle, and then calculates the normalized amplitude of the four harmonics and the base wave, as well as the signal distortion. MCU1 transmits signal characteristic data to MCU2 through serial port. After the waveform is recovered by MCU2, MCU1 displays the signal on screen and transmits it to APP display on mobile phone via Bluetooth. The test results show that the system has good stability and high measurement accuracy.