WIDEBAND ANTENNA HAVING A BLOCKING BAND
A wideband antenna including a ground element, and an antenna body provided on the ground element with a predetermined distance. The antenna body includes a feed element and a dielectric substrate, wherein an annular passive element is provided on the top surface of the dielectric substrate with a predetermined gap from the feed element. A plural short-circuit pins are equally spaced on the outer periphery of the passive element, whereby the passive element and the ground element 17 are connected by the short-circuit pins. A slit is formed on the passive element in the vicinity of the short-circuit pins. Since the slit is formed on the passive element, a resonance circuit having a resonance frequency dependant on the shape of the slit is formed on the passive element in the vicinity of the slit, whereby the radiation of the frequency component from the feed element is prevented.
1 . A wideband antenna comprising a feed element provided on a ground element, a passive element that surrounds the feed element with a gap, and plural short-circuit pins that connect the passive element to the ground element, wherein
a slit that generates a blocking band for preventing the radiation of a specific frequency is formed on the passive element in the vicinity of the connection pins.
2 . The wideband antenna according to claim 1 , wherein
the feed element and the passive element have a concentric shape, wherein the connection pins are equally spaced on the outer periphery of the passive element.
3 . The wideband antenna according to claim 2 , wherein
the slit is an arc concentric with the passive element.
4 . The wideband antenna according to claim 2 , wherein
the length of the slit is about λ/2, when the wavelength of the central frequency of the blocking band is defined as λ.
5 . The wideband antenna according to claim 3 , wherein
the length of the slit is about λ/2, when the wavelength of the central frequency of the blocking band is defined as λ.
6 . The wideband antenna according to claim 2 , wherein
the slit includes a pair of L-shaped slit and a reversed L-shaped slit.
7 . The wideband antenna according to claim 6 , wherein
the length of each of the L-shaped slit and the reversed L-shaped slit is about λ/4, when the wavelength of the central frequency of the blocking band is defined as λ.
8 . The wideband antenna according to claim 1 , wherein
the passive element is mounted on a surface of a dielectric substrate.
9 . The wideband antenna according to claim 2 , wherein
the passive element is mounted on a surface of a dielectric substrate.
10 . The wideband antenna according to claim 3 , wherein
the passive element is mounted on a surface of a dielectric substrate.
11 . The wideband antenna according to claim 4 , wherein
the passive element is mounted on a surface of a dielectric substrate.
12 . The wideband antenna according to claim 5 , wherein
the passive element is mounted on a surface of a dielectric substrate.
13 . The wideband antenna according to claim 6 , wherein
the passive element is mounted on a surface of a dielectric substrate.
14 . The wideband antenna according to claim 1 , wherein
the feed element is a body of revolution of a logarithm curve that expands from the ground element toward the passive element.
15 . The wideband antenna according to claim 2 , wherein
the feed element is a body of revolution of a logarithm curve that expands from the ground element toward the passive element.
16 . The wideband antenna according to claim 3 , wherein
the feed element is a body of revolution of a logarithm curve that expands from the ground element toward the passive element.
17 . The wideband antenna according to claim 4 , wherein
the feed element is a body of revolution of a logarithm curve that expands from the ground element toward the passive element.
18 . The wideband antenna according to claim 5 , wherein
the feed element is a body of revolution of a logarithm curve that expands from the ground element toward the passive element.
19 . The wideband antenna according to claim 6 , wherein
the feed element is a body of revolution of a logarithm curve that expands from the ground element toward the passive element.
20 . The wideband antenna according to claim 14 , wherein
the logarithm curve is
x=−x 0 exp[− t ( z−z 1 )]+ x 0 +x 1 .
t=[ ln(1+ x 1 /x 0 )/[ z 1 −z 2 ]
between a point (x 1 , 0, z 1 ) and a point (0, 0, z 2 ).
21 . The wideband antenna according to claim 15 , wherein
the logarithm curve is
x=−x 0 exp[− t ( z−z 1 )]+ x 0 +x 1
t=[ ln(1+ x 1 /x 0 )[ z 1 −z 2 ]
between a point (x 1 , 0, z 1 ) and a point (0, 0, z 2 ).
22 . The wideband antenna according to claim 16 , wherein
the logarithm curve is
x=−x 0 exp[− t ( z−z 1 )]+ x 0 +x 1
t=[ ln(1+ x 1 /x 0 )/[ z 1 −z 2 ]
between a point (x 1 , 0, z 1 ) and a point (0, 0, z 2 ).
23 . The wideband antenna according to claim 17 , wherein
the logarithm curve is
x=−x 0 exp[− t ( z−z 1 )]+ x 0 +x 1
t=[ ln(1+ x 1 /x 0 )[ z 1 −z 2 ]
between a point (x 1 , 0, z 1 ) and a point (0, 0, z 2 ).
24 . The wideband antenna according to claim 18 , wherein
the logarithm curve is
x=−x 0 exp[− t ( z−z 1 )]+ x 0 +x 1
t=[ ln(1+ x 1 /x 0 )/[ z 1 −z 2 ]
between a point (x 1 , 0, z 1 ) and a point (0, 0, z 2 ).
25 . The wideband antenna according to claim 19 , wherein
the logarithm curve is
x=−x 0 exp[− t ( z−z 1 )] x 0 +x 1
t=[ ln(1+ x 1 /x 0 )/[ z 1 −z 2 ]
between a point (x 1 , 0, z 1 ) and a point (0, 0, Z 2 ).