Journal of the Korea Institute of Military Science and Technology (한국군사과학기술학회지)

The Korea Institute of Military Science and Technology (한국군사과학기술학회)
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A Design Method for Pre-Distortion Compensation of SAR Chirp Signal based on Envelop Sampling and Interpolation Filter

위성 탑재 영상레이다 첩 신호의 전치왜곡 보상을 위한 포락선 샘플링 및 보간 필터 기반의 설계 기법

  • Lee, Young-Bok (Defense and Space Technology Center, Agency for Defense Development)
  • 이영복 (국방과학연구소 국방우주기술센터)
  • Received : 2022.03.18
  • Accepted : 2022.07.15
  • Published : 2022.08.05
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Abstract

The synthetic aperture radar(SAR) is an equipment that can acquire images in all weathers day and night based on radar signals. The on-board processor of satellite SAR generates transmission signal by digital signal processing, converts it into an analog signal and transmits to antenna. Until the transmission signal generated by on-board processor is output, the signal passes the transmission cables and analog devices. At this time, these hardware distort the signal and makes SAR performance worse. To improve the performance, pre-distortion technique is used. But, general pre-distortion using taylor series is not sufficient to compensate for the distortion. This paper suggests transmit signal design method with improved pre-distortion. This paper uses envelop sampling method and interpolation filter for frequency domain compensation. The proposed method accurately compensates the hardware distortion and reduces resource usage of FPGA. To analyze proposed method's performance, IRF characteristics are compared when the proposed method applies to signal with errors.

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References

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