Design and Performance Analysis of Zoom-FFT Based FMCW Radar Level Meter

Zoom-FFT 기반 FMCW 레이더 레벨미터의 설계 및 성능분석

  • 누완 (공주대학교 전기전자제어공학부) ;
  • 김원호 (공주대학교 전기전자제어공학부)
  • Received : 2014.05.06
  • Accepted : 2014.05.28
  • Published : 2014.06.30

Abstract

This paper presents design of a FMCW (Frequency Modulated Continuous Wave) level meter as well as simulation result of the designed system. The system is designed to measure maximum range of 20m since FMCW radar can be used for measuring short range distance. The distance is measured by analyzing the beat signal which is generated as result of mixing transmitting signal with the reflected received signal. The Fast Fourier Transform is applied to analyze the beat signal for calculating the displacement and Zoom FFT technique is used to minimize measurement error as well as increase the resolution of the measurement. The resolution of the measurement of the designed system in this paper is 2.2mm and bandwidth of 1.024GHz is used for simulation. Thus the simulation results are analyzed and compared in various conditions in order to get a comprehensive idea of frequency resolution and displacement resolution.

본 논문은 FMCW(Frequency Modulated Continuous Wave) 레이더 레벨 측정기 설계와 시뮬레이션을 통한 성능분석에 대하여 기술한다. 설계된 레벨미터는 FMCW radar를 이용하여 최대 20m 거리를 측정하며, 거리 계산을 위한 비트신호 분석기법으로 FFT(Fast Fourier Transform)와 Zoom-FFT를 적용하였다. 성능 분석을 위해 시뮬레이션을 통하여 두가지 기법을 비교 분석한 결과, 측정오류를 최소화하고 측정의 분해능을 향상시키기 위해서는 Zoom-FFT 기법이 보다 적절한 기법임을 확인하였다. 시뮬레이션은 주파수 분해능과 측정거리 분해능의 최적 값을 얻기 위해 다양한 조건에서 분석하였고, 1.024GHz 주파수 조건에서 2.2mm의 측정 분해능을 확인하였다.

Keywords

References

  1. Guilin Zheng, Hongyan Zong,Xiangtao Zhuan, Lijuan Wang,"High-Accuracy Surface-Perceiving Water Level Gauge With Self-Calibration for Hydrography", Sensors Journal of EEE , Vol. 10, pp. 1893-1900, 2010 https://doi.org/10.1109/JSEN.2010.2050138
  2. Weiss, Knochel, Reinhard, "A sub-millimeter accurate microwave multilevel gauging system for liquids in tanks", IEEE Transactions on Microwave Theory and Techniques, Vol. 49, pp 381-384, 2001 https://doi.org/10.1109/22.903101
  3. Gulden, Vossiek, Stelzer, "Application of state-space frequency estimation to a 24-GHz FMCW tank level gauging system", Conference on Microwave, Vol. 3, pp. 995-998, 2003
  4. Eugin Hyun, Sang-Dong Kim, Yeong-Hwan Ju, Jong-Hun Lee, "FPGA based signal processing module design and implementation for FMCW vehicle radar systems", IEEE CIE International Conference on Radar, Vol. 1, pp 273-275, 2011
  5. Hyun, Jonghun Lee, "Moving target range detection algorithm for FMCW radar" 14th International Radar Symposium (IRS), Vol. 2, pp. 758-761, 2013
  6. Hai Chen, Yan Li, Xin-Min Wang, "Digital Signal Processing for A Level Measurement System Based on FMCW Radar", IEEE International Conference on Control and Automation, pp 2843-2847, 2007
  7. Suk-Jun Ji, Woo-Jin Choi, Kyung-Yup Kim, Lee, "A study on the precise distance measurement for radar level transmitter of FMCW type using correlation analysis method", 13th International Symposium on Advanced Intelligent Systems (ISIS), pp 2009-2014, 2012
  8. Armbrecht, Zietz, Denicke, Rolfes, "Antenna Impact on the Gauging Accuracy of Industrial Radar Level Measurements", IEEE Transactions on Microwave Theory and Techniques, vol. 59, pp 2554-2562, 2011 https://doi.org/10.1109/TMTT.2011.2163075
  9. Weiss, " Low-cost, low-power nanosecond pulse radar for industrial applications with mm accuracy", International Symposium on Electron Devices for Microwave and Optoelectronic Applications, pp. 199-204, 2001.
  10. Stuchly, Hamid, Andres, "Microwave Surface Level Monitor", IEEE Transactions on Industrial Electronics and Control Instrumentation, vol. 18, pp. 85-92, 2006