Null-fill antenna, omni antenna, and radio communication equipment
AssigneeNEC Corporation
InventorNorihiko Oomuro
Life of this patent
Estimating the term…
Abstract
A wide-angle null-fill antenna with no null in the depression angle range, an omni antenna using the same, and radio communication equipment. A null-fill antenna comprises a first antenna array including antenna elements arranged with a prescribed point as the center, and a second antenna array having amplitude characteristics substantially equal to those of the antenna elements forming the first antenna array. The first antenna array is excited so that the excitation amplitude distribution is to have symmetry with respect to the prescribed point, while the excitation phase distribution is to have point symmetry with respect to the prescribed point. The phase center of the first antenna array is substantially coincident with that of the second antenna array.
Claims5
A null-fill antenna comprising:
- a first antenna array including antenna elements arranged with a prescribed point as the center;
- and
- a parasitic element which is spaced apart from the phase center of the first antenna array substantially not more than one wavelength forwardly in the vertical direction with respect to the first antenna array, said parasitic element being indirectly excited by radiation waves from the first array;
- wherein:
- the first antenna array is excited so that the excitation amplitude distribution is to have symmetry with respect to the prescribed point, while the excitation phase distribution is to have substantially point symmetry with respect to the prescribed point;
- and
- the phase center of the first antenna array is substantially coincident with that of the parasitic element.
Dependencies are inferred from the claim text.