摘要 輻射校正為利用多時期合成孔徑雷達影像於變遷偵測以及定量遙感必要步驟。本論文研發功率可調主動式雷達校正器，其目的為:第一點是為了在控制點過飽和時可以調整主動式雷達校正器放大功率。第二點是考量機載合成孔徑雷達系統的近距點、遠距點距離變化較大，所以架設在不同距離，雷達系統接收到的訊號差異也比較大，進而調整主動式雷達校正器功率。第三點我們可以利用功率可調加上時間延遲的主動式雷達校正器，在室內就可以模擬雷達回波訊號給發展中的雷達系統進行測試與性能分析。本研究的功率可調主動式雷達校正器在經過穩定度量測後，得到增益的穩定度 ，且功率可調雷達截面積的實驗量測與理論值差異小於0.2dB，所以可以推論功率可調主動式雷達校正器可以提供精確的功率給雷達系統做輻射校正。 Abstract Radiometric calibration is essential for multi-temporal SAR image change detection and quantitative remote sensing. This study focuses on developing and implementing a power-tuning active radar calibrator (ARC). The objects are:First is tuning ARC’s power for overload of critical point in SAR image.Second is that difference of ARC’s receiving signal is large at different range in airplane SAR, so we want to tune ARC’s power.Third is the power-tuning and time-delay ARC can be used to simulate radar transmitting and receiving signal in order to test and analyze the characteristic for purpose of developing a new radar system.After extensive measurements by the power-tuning ARC, the gain stability is less than 0.6dB. The differences between power-tuning RCS experimental results and theoretical values are less than 0.2dB. Hence, the new power-tuning ARC offers very precise radiometric calibration for radar system.
