PURPOSE: To suppress the retroradiation caused at the periphery of the shadow boundary and the diffracted wave, by attaching the electric wave absorber onto the inner wall of the masking shield and at the same time reducing the electric field at the tip of the masking shield by the length of the masking shield.
CONSTITUTION: The electric wave absorber 5 is attached onto the inner wall of the masking shield 4 in an appropriate width to absorb the spill-over power of the primary radiator 3 which contributes to the radiation property at the periphery of the shadow boundary. As a result, the radiation property can be reduced at the shadow boundary and its periphery. Furthermore, the electric field at the tip P of the shield 4 can be reduced over the circle circumference with use of the length (h) of the shield 4 which is obtained from the equation. Accordingly, the retroradiation property can be suppressed. In the equation, D shows the aperture diameter of the reflector 2, λ is the wavelength, and i=3, 5... respectively.
USHIGOME HIROSHI
KONNO YOSHIROU
MITSUBISHI ELECTRIC CORP
| JPS4957748A | 1974-06-05 |