Journal of Advanced Navigation Technology (한국항행학회논문지)

The Korean Navigation Institute (한국항행학회)
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Design of FMCW Radar Signal Processor for Human and Objects Classification Based on Respiration Measurement

호흡 기반 사람과 사물 구분 가능한 FMCW 레이다 신호처리 프로세서의 설계

  • Lee, Yungu (School of Electronics and Information Eng., Korea Aerospace University) ;
  • Yun, Hyeongseok (School of Electronics and Information Eng., Korea Aerospace University) ;
  • Kim, Suyeon (School of Electronics and Information Eng., Korea Aerospace University) ;
  • Heo, Seongwook (School of Electronics and Information Eng., Korea Aerospace University) ;
  • Jung, Yunho (School of Electronics and Information Eng., Korea Aerospace University)
  • 이윤구 (한국항공대학교 항공전자정보공학부) ;
  • 윤형석 (한국항공대학교 항공전자정보공학부) ;
  • 김수연 (한국항공대학교 항공전자정보공학부) ;
  • 허성욱 (한국항공대학교 항공전자정보공학부) ;
  • 정윤호 (한국항공대학교 항공전자정보공학부)
  • Received : 2021.08.03
  • Accepted : 2021.08.24
  • Published : 2021.08.31
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Abstract

Even though various types of sensors are being used for security applications, radar sensors are being suggested as an alternative due to the privacy issues. Among those radar sensors, PD radar has high-complexity receiver, but, FMCW radar requires fewer resources. However, FMCW has disadvantage from the use of 2D-FFT which increases the complexity, and it is difficult to distinguish people from objects those are stationary. In this paper, we present the design and the implementation results of the radar signal processor (RSP) that can distinguish between people and object by respiration measurement using phase estimation without 2D-FFT. The proposed RSP is designed with Verilog-HDL and is implemented on FPGA device. It was confirmed that the proposed RSP includes 6,425 LUT, 4,243 register, and 12,288 memory bits with 92.1% accuracy for target's breathing status.

보안 시스템에는 다양한 센서가 사용되고 있지만, 사생활 문제가 논란이 됨에 따라 레이다 센서가 대안으로 제시되고 있다. 그 중 PD (Pulse Doppler) 레이다는 짧은 펄스를 사용함으로써 수신부 복잡도가 증가하는 문제가 존재하나, FMCW (Frequency modulated continuous wave) 레이다는 그러한 제한이 적다는 장점이 있다. 그러나, FMCW 레이다는 2D-FFT (2-dimensional fast Fourier transform)를 사용하므로 기존의 센서에 비해서 상대적으로 높은 복잡도를 가지며, 정지해있는 표적에 대해 사람과 사물을 구분하기 어려운 단점이 있다. 따라서 본 논문에서는 1D-FFT와 위상 변화만으로 호흡 여부를 확인하여 사람과 사물을 구분할 수 있는 레이다 신호처리 프로세서의 설계 및 구현 결과를 제시한다. 제안된 신호처리 프로세서는 Verilog-HDL을 기반으로 설계하여 FPGA 디바이스에 기반하여 구현 및 검증하였다. LUT (Look up table) 6,425개, register 4,243개, 12,288개의 memory bit로 구현하여 92.1%의 정확도로 대상의 호흡 여부를 확인할 수 있음을 확인하였다.

Keywords

Acknowledgement

본 논문은 2021년도 정부 (과학기술정보통신부)의 재원으로 정보통신기획평가원의 지원을 받아 수행되었으며 (No. 2019-0-00056, 2020-0-00201), CAD tool은 IDEC에 의해 지원되었음.

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