| 摘要 |
PURPOSE:To simplify the device and make mass production possible, by arranging the helical antenna at the focus of the paraboloid reflective mirror. CONSTITUTION:Radio wave (a) is reflected by paraboloid reflective mirror 1 and is incident to helical antenna 3 arranged at the focus of paraboloid reflective mirror 1 and goes along helicoid 5. When the length of one turn along helicoid 5, the putch of helicoid 5, and the wavelength of receiving radio wave (a) are denoted as (l), (p), and lambda respectively, the same phase is obtained in the axial direction of helicoid 5 for radio waves which satisfy the condition indicated by expression l-p=nlambda (n is an integer), and the antenna gain is obtained. |
