| 摘要 |
PURPOSE:To negate the reflected wave caused by the opening cover and thus to prevent the deterioration of the oval polarized wave rate by providing the opening covers at the two areas in the path of the electric wave of the horn antenna. CONSTITUTION:The wave sent from circular-rectangular wave guide converter 5 passes through polarized branching filter 4, circular polarized wave generator 3, conical horn 2 plus opening cover 1a and 1b in that order and then radiated into the free space in the form of the circular polarized wave. The part of the incident waves is reflected by cover 1a, and part of the waves passed through cover 1a is reflected again by cover 1b. In this connection, the space between 1a and 1b is selected to the length of the odd-multiplication of 1/4 waveform or 1/4 waveform. At the same time, the relationship between reflection coefficient Pa of cover 1a and reflection coefficient Pb of cover 1b is set to Pb=Pa/(1-Pa)<2>. As a result, the reflected waves through the two covers can be negated completely. |
