衛星是在當今世界中扮演重要的角色，而天線是連接衛星與地面的橋梁。如果能夠知道天線正在跟哪顆衛星通訊，我們就能得到更多情報，這對國防安全是有幫助的。天線接收的基本原理是將衛星發射訊號，在天線的表面反射到天線的感應器來接收衛星上的資料。為了降低難度，本研究只偵測碟型天線(圓)的方向。這項研究的目的是利用遙測影像偵測碟型天線的方向，但我們同時使用衛星影像及無人飛行器影像。無人飛行器影像比衛星影像成本低廉以及具有高解析度，但衛星影像的優點在可以監控受管制區域，特別是在其他國家。本研究的基本步驟為: 首先，先對衛星影像做影像前處理。第二，使用霍夫轉換去偵測碟型天線的邊界。最後，利用幾何關係估計碟行天線的方向。實驗成果顯示此方法的可行性。;Nowadays, satellite technologies become more and more important in our daily life. To communicate with satellites, satellite antennas will point to those satellites and transmit and receive signal or data. We may acquire some information of the purposes of the antennas if we know which satellites they communicate with. This information may be helpful for national defense and security. To simplify this problem, we only consider the facing direction of dish antenna, so the goal of this study is to estimate azimuth and orientation angles of dish antenna from remote sensing image. Both images from satellites and Unmanned Aerial Vehicle (UAV) are used. The UAV images are inexpensive with higher resolution compare to satellite imagery. On the other hand, the advantage of satellites is they can access images from restricted area, especially in other country. The detection of antenna orientation has three steps. First, image pre-processing technique is applied to satellite image. Secondly, Hough transform is adopted to detect the edge of dish antenna. Finally, the orientation is estimated by geometry model. Our experiments show satisfied results for the estimation.
