| 摘要 |
1,223,778. Aerials. CHU ASSOCIATES Inc. 17 March, 1969, No. 13905/69. Heading H4A. A wide-band omni-directional aerial with an upwardly directed radiation diagram comprises a cylindrical conductive member 1, 1<SP>1</SP> having a length corresponding to a half-wavelength at the low frequency end of said band. Current suppressing means 4 are disposed along said member at a distance from one end corresponding to a half-wavelength at the high frequency end of said band. A ground plane comprising co-planar conductors 7, 7 and 7<SP>1</SP>, 71 of different lengths provides diametric paths corresponding to half-wavelengths at the low and high frequency ends of said band. A slot 3 is defined between the ground plane and the aforesaid one end of the member 1, 1<SP>1</SP> and power at different frequencies within said band is fed across it. As described, the member 1, 1<SP>1</SP> has a section 1<SP>1</SP> which is smaller in diameter than another section 1. The means 4 comprises a plurality of conductive stubs which conically surround the upper portion of the section 1. Radially extending conductors 7, 7 and 7<SP>1</SP>, 7<SP>1</SP> are carried on a ring 5 insulatingly spaced from the end of the section 1. Power is fed across the slot 3 by a coaxial line 2, 2<SP>1</SP>, an impedance matching element 6 being provided. |
