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Leakage Signal Canceller and Adaptive Algorithm in Millimeter-Wave Seeker

밀리미터파 탐색기 내 누설신호 상쇄기 및 적응형 알고리즘에 관한 연구

  • Received : 2018.12.03
  • Accepted : 2019.01.09
  • Published : 2019.01.31

Abstract

A leakage canceller and adaptive algorithm for FMCW Radar is presented. Because a strong leakage signal causes various problems in the transceiver and digital processor, specific FMCW radars are in need of a leakage canceller. The leakage canceller has an adaptive structure and the algorithm calculates the prediction vector and learns the adaptive coefficient simultaneously. The proposed algorithm an improvement of 10 dB in the cancellation performance.

Keywords

Leakage Cancellation;Millimeter-Wave Seeker;FMCW Radar;Adaptive Algorithm;Isolation

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그림 1. 밀리미터파 탐색기의 누설신호 경로 Fig. 1. Path of leakage signal in millimeter-wave seeker.

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그림 2. 누설신호 상쇄기 블록 다이어그램 Fig. 2. Block diagram of leakage signal canceller.

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그림 3. (a) 고정된 학습적응 계수에 따른 발생 오차, (b) 그래프 확대 후 Fig. 3. (a) Error dispersion with fixed adaptation coefficients, (b) Graph zoom in.

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그림 5. 학습적응 계수 수렴 그래프 Fig. 5. Convergence of adaptation coefficient value.

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그림 6. 누설/상쇄신호 주파수 스펙트럼 그래프 Fig. 6. Spectrum of leakage and cancelled signals.

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그림 7. 송신파형 초반 구간 누설 성능 비교 그래프 Fig. 7. Early phase leakage cancellation performances.

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그림 8. 비트주파수에 따른 표적신호 감쇄 그래프 Fig. 8. Target signal degradation as per beat frequency.

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그림 4. 제안하는 적응형 알고리즘 순서도 Fig. 4. Proposed adaptive algorithm flowchart.

표 1. 누설선로 길이 및 신호세기 Table 1. Path length and power of leakage signals.

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