Antenna structure
An antenna structure ( 10 ) includes an antenna feed-in element ( 1 ), a first antenna trace element ( 2 ), a second antenna trace element ( 3 ), a supporting element ( 4 ), a grounded-short-circuit element ( 5 ), a third antenna trace element ( 6 ) and a fourth antenna trace element ( 7 ). The first antenna trace element ( 2 ), the second antenna trace element ( 3 ), the third antenna trace element ( 6 ) and the fourth antenna trace element ( 7 ) which have vertical segments in different lengths form a multi-trace planar inverted-F antenna to obtain the best bandwidth covering the full band, so that the height of the antenna structure ( 10 ) is lower, the length is shorter and the structure is denser. The impedance matching of the antenna structure ( 10 ) is controlled easily. No external matching element is required. With the multi-trace and grounded-short-circuit design of the antenna structure ( 10 ), the better resonance in the LTE full band is obtained.
1. An antenna structure comprising:
a planar antenna feed-in element;
a first planar antenna trace element connected to a first side of the antenna feed-in element and oriented at a first oblique angle to the planar antenna feed-in element;
a second planar antenna trace element connected to a second side of the planar antenna feed-in element oriented at a second oblique angle to the planar antenna feed-in element, the first planar antenna trace element oriented in a direction different from a direction in which the second planar antenna trace element is oriented so that the first planar antenna trace element and the second planar antenna trace element form an opening;
a planar supporting element connected at a first side of the planar supporting element to a third side of the planar antenna feed-in element;
a planar grounded-short-circuit element connected at a first side to a second side of the planar supporting element;
a third antenna trace element connected to a third side of the planar supporting element; and
a fourth antenna trace element connected at a first side connected to a second side of the grounded-short-circuit element.
2. The antenna structure of claim 1 , wherein the planar antenna feed-in element comprises:
a first gap, the first gap arranged at one side of the planar antenna feed-in element, the first gap having an L-shape;
a first protruding part arranged above the first gap;
a second gap arranged at another side of the planar antenna feed in element; and a second protruding part arranged above the second gap; and wherein another side of the planar antenna feed-in element is electrically connected to at least one of a circuit board and a cable.
3. The antenna structure of claim 2 , wherein a length of the first gap is longer than a length of the second gap.
4. The antenna structure of claim 2 , wherein the first planar antenna trace element is connected to the first protruding part.
5. The antenna structure of claim 4 , wherein a width of the first planar antenna trace element is equal to a length of the first protruding part.
6. The antenna structure of claim 2 , wherein the second planar antenna trace element is connected to the second protruding part.
7. The antenna structure of claim 6 , wherein a width of the second planar antenna trace element is equal to a length of the second protruding part.
8. The antenna structure of claim 1 , wherein the opening tapers inward in the direction of the planar antenna feed-in element.
9. The antenna structure of claim 1 , wherein the planar supporting element comprises a third gap and a third protruding part, and wherein the third gap and the third protruding part are arranged at one side of the supporting element.
10. The antenna structure of claim 9 , wherein the grounded-short-circuit element is connected to the third protruding part arranged at one side of the planar supporting element.
11. The antenna structure of claim 10 , wherein the grounded- short-circuit element comprises a broadside arranged at one side of the grounded-short-circuit element and electrically connected to a circuit board, the broadside comprising a stair-step shape.
12. The antenna structure of claim 11 , wherein the fourth antenna trace element comprises:
a first sheet connected to the broadside of the grounded-short-circuit element;
a second sheet, wherein one side of the first sheet is connected to the second; and
a third sheet, wherein one side of the second sheet is connected to the third sheet and wherein the third sheet is in a number 7 shape.
13. The antenna structure of claim 12 , wherein the first sheet and the second sheet comprise rectangular plates.
14. The antenna structure of claim 1 , wherein the third antenna trace element comprises a U-shaped plate.
15. An antenna comprising:
an antenna feed-in element;
a first antenna trace element connected to a first edge of the antenna feed-in element and oriented at a first oblique angle to the antenna feed-in element;
a second antenna trace element connected to a second edge of the antenna feed-in element and oriented at a second oblique angle to the antenna feed-in element, the first edge of the antenna feed-in element located opposite the second edge of the antenna feed-in element;
a supporting element connected at a first edge of the supporting element to a third edge of the antenna feed-in element;
a grounded short circuit element connected at a first edge to a second edge of the supporting element;
a third antenna trace element connected to a third edge of the supporting element;
and
a fourth antenna trace element connected at a first edge connected to a second edge of the grounded short circuit element.
16. The antenna of claim 15 , wherein the supporting element is generally orthogonal to the antenna feed-in element.
17. The antenna of claim 15 , wherein the grounded short circuit element is generally parallel to the third antenna trace element.
18. The antenna of claim 15 , wherein a first portion of the fourth antenna trace element is generally orthogonal to the grounded short circuit element.
19. The antenna of claim 18 , wherein a second portion of the fourth antenna trace element is generally parallel to the grounded short circuit element.
20. The antenna of claim 18 , wherein the size of the first oblique angle is substantially equal to the size of the second oblique angle.