Antenna apparatus and wireless communication apparatus
An antenna apparatus includes a ground substrate, a feeding point provided on the ground substrate, a first loop antenna of which one end is electrically connected to the feeding point and of which another end is electrically connected to the ground substrate and moreover which operates at a first frequency, and a second loop antenna of which both ends are respectively connected to a first end point and a second end point of the first loop antenna and which operates at a second frequency. A space between the first end point and the second end point forms a gap with a range in which the first loop antenna is capable of resonating at the first frequency.
1. An antenna apparatus, comprising:
a ground substrate;
a feeding point provided on the ground substrate;
a first loop antenna of which one end is electrically connected to the feeding point and of which another end is electrically connected to the ground substrate and moreover which operates at a first frequency; and
a second loop antenna of which both ends are respectively connected to a first end point and a second end point of the first loop antenna and which operates at a second frequency, wherein
a space between the first end point and the second end point forms a gap with a range in which the first loop antenna is capable of resonating at the first frequency.
2. The antenna apparatus according to claim 1 , wherein
the space between the first end point and the second end point forms a gap that is 1/50 of the first frequency.
3. The antenna apparatus according to claim 1 , wherein
the first end point and the second end point are provided in a range of ¼ or less of the first frequency from the feeding point.
4. The antenna apparatus according to claim 1 , wherein
a capacitor or an inductor is provided on an electric path between the first loop antenna and the ground substrate.
5. The antenna apparatus according to claim 1 , wherein
a switch which switches between the capacitor and the inductor to be connected to the feeding point is interposed between the feeding point and the first loop antenna.
6. The antenna apparatus according to claim 1 , wherein
the first loop antenna and the ground substrate are electrically connected to each other by a spring contact.
7. The antenna apparatus according to claim 1 , wherein
the first loop antenna is further electrically connected to the ground substrate at one or more locations on the first loop antenna.
8. The antenna apparatus according to claim 1 , wherein
the first loop antenna is provided with two or more second loop antennas which are operated by radio waves with frequencies that differ from each other.
9. The antenna apparatus according to claim 1 , wherein
the antenna apparatus is mounted to a mobile terminal apparatus, and
at least a part of the first loop antenna is formed of a metal frame which constitutes an exterior of the mobile terminal apparatus.
10. The antenna apparatus according to claim 1 , wherein
the antenna apparatus is mounted to a mobile terminal apparatus, and
at least a part of the second loop antenna is formed using Laser Direct Structuring (LDS) or a flexible substrate.
11. The antenna apparatus according to claim 1 , further comprising a first conductor device of which one end is connected to a connecting point of the first loop antenna and which is parallel to the ground substrate, wherein
a length from a contact point which connects the other end of the first loop antenna and the ground substrate to each other to another end of the first conductor device via the first loop antenna is ¼ wavelength of a third frequency.
12. A wireless communication apparatus mounted with the antenna apparatus according to claim 1 .