Noise-immune miniaturized antenna
Technologies directed to a noise-immune miniaturized antenna (NIMA) structure in a main logic board (MLB) and diverting surface currents from the MLB to a metal structure to reduce noise coupling from a chipset on the MLB to the NIMA structure are described. The NIMA structure is located at a side of the MLB and includes a first tuning component coupled to a distal end of a radiating arm of the NIMA structure and a second tuning component coupled to a distal end of a shorting arm of the NIMA structure. The NIMA structure radiates in a first frequency range and a second frequency range. A conductive fastener couples the MLB to a metal structure to divert surface currents from the MLB to the metal structure.
1 . A wireless device comprising:
a metal structure;
a wireless local area network (WLAN) radio;
a circuit board comprising a ground plane and an inverted-F antenna (IFA) structure located at an opening in the ground plane, the opening being located at a side of the ground plane, wherein the IFA structure comprises:
a feed point coupled to the WLAN radio, wherein the feed point is located at a first edge of the ground plane opposite to the opening;
a first grounding point located at a second edge of the ground plane adjacent to the opening;
a second grounding point located at the first edge, the second grounding point being located farther away from the side than the feed point;
a feed arm coupled to the feed point;
a radiating arm coupled to the feed arm and the first grounding point;
a shorting arm coupled to the radiating arm and the second grounding point;
a first tuning component coupled to a distal end of the radiating arm and the first grounding point, wherein the first tuning component is configured to cause the IFA structure to radiate electromagnetic energy in a first frequency range; and
a second tuning component coupled to a distal end of the shorting arm and the second grounding point, wherein the second tuning component is configured to cause the IFA structure to radiate electromagnetic energy in a second frequency range.
2 . The wireless device of claim 1 , wherein the IFA structure is located at a second side of the ground plane, wherein the side and the second side are adjacent sides.
3 . The wireless device of claim 1 , wherein a first portion of the radiating arm is parallel to a third edge of the ground plane, the third edge being adjacent the first edge and opposite the second edge.
4 . The wireless device of claim 1 , further comprising:
a heatsink; and
one or more conductive spring clips coupled between the circuit board and the heatsink, wherein the one or more conductive spring clips is to divert surface currents from the circuit board, caused by the IFA structure, to the heatsink to minimize noise coupling from a circuit of the circuit board to the IFA structure.
5 . The wireless device of claim 1 , wherein the IFA structure fits within the opening having a height of 7 millimeters (mm) and a width of 8 mm.
6 . The wireless device of claim 1 , wherein the IFA structure is less than 10 millimeters in a first dimension and less than 10 millimeters in a second, perpendicular dimension.
7 . The wireless device of claim 1 , wherein the IFA structure fits within the opening having a height of less than 10 millimeters (mm) and a width of less than 10 mm.
8 . The wireless device of claim 1 , further comprising an impedance-matching circuit coupled between the WLAN radio and the feed point, wherein the first tuning component comprises a capacitor, and wherein the second tuning component comprises an inductor.
9 . The wireless device of claim 1 , further comprising:
active circuitry located in a first region of the circuit board, wherein the IFA structure is located in a second region of the circuit board and configured to generate a surface current with a null in the first region.
10 . A circuit board comprising:
a ground plane; and
an inverted-F antenna (IFA) structure located at an opening in the ground plane, the opening being located at a side of the ground plane, wherein the IFA structure comprises:
a feed point located at a first edge of the ground plane opposite to the opening;
a first grounding point located at a second edge of the ground plane adjacent to the opening;
a second grounding point located at the first edge, the second grounding point being located farther away from the side than the feed point;
a feed arm coupled to the feed point;
a radiating arm coupled to the feed arm and the first grounding point;
a shorting arm coupled to the radiating arm and the second grounding point;
a first tuning component coupled to a distal end of the radiating arm and the first grounding point, wherein the first tuning component is configured to cause the IFA structure to radiate electromagnetic energy in a first frequency range; and
a second tuning component coupled to a distal end of the shorting arm and the second grounding point, wherein the second tuning component is configured to cause the IFA structure to radiate electromagnetic energy in a second frequency range.
11 . The circuit board of claim 10 , wherein the IFA structure is located at a second side of the ground plane, wherein the side and the second side are adjacent sides.
12 . The circuit board of claim 10 , wherein a first portion of the radiating arm is parallel to a third edge of the ground plane, the third edge being adjacent the first edge and opposite the second edge.
13 . The circuit board of claim 10 , wherein the IFA structure fits within the opening having a height of 7 millimeters (mm) and a width of 8 mm.
14 . The circuit board of claim 10 , wherein the IFA structure is less than 10 millimeters in a first dimension and less than 10 millimeters in a second, perpendicular dimension.
15 . The circuit board of claim 10 , wherein the IFA structure fits within the opening having a height of less than 10 millimeters (mm) and a width of less than 10 mm.
16 . The circuit board of claim 10 , further comprising an impedance-matching circuit coupled to the feed point, wherein the first tuning component comprises a capacitor, and wherein the second tuning component comprises an inductor.
17 . The circuit board of claim 10 , further comprising:
active circuitry located in a first region of the circuit board, wherein the IFA structure is located in a second region of the circuit board and configured to generate a surface current with a null in the first region.
18 . An electronic device comprising:
a radio;
a circuit board comprising a ground plane and an inverted-F antenna (IFA) structure located at an opening in the ground plane, the opening being located at a side of the ground plane, wherein the IFA structure comprises:
a feed point coupled to the radio, wherein the feed point is located at a first edge of the ground plane opposite to the opening;
a first grounding point located at a second edge of the ground plane adjacent to the opening;
a second grounding point located at the first edge, the second grounding point being located farther away from the side than the feed point;
a feed arm coupled to the feed point;
a radiating arm coupled to the feed arm and the first grounding point;
a shorting arm coupled to the radiating arm and the second grounding point;
a first tuning component coupled to a distal end of the radiating arm and the first grounding point, wherein the first tuning component is configured to cause the IFA structure to radiate electromagnetic energy in a first frequency range; and
a second tuning component coupled to a distal end of the shorting arm and the second grounding point, wherein the second tuning component is configured to cause the IFA structure to radiate electromagnetic energy in a second frequency range.
19 . The electronic device of claim 18 , wherein the IFA structure is located at a second side of the ground plane, wherein the side and the second side are adjacent sides.
20 . The electronic device of claim 18 , wherein a first portion of the radiating arm is parallel to a third edge of the ground plane, the third edge being adjacent the first edge and opposite the second edge.