Multiple PIFA/IFA type antennas operating at the same frequency including short pins to minimize antenna separation
An antenna system includes a plurality of PIFA/IFA type wherein each of the plurality of antennas have either a same short pin or different short pins located together to minimize antenna separation between the plurality of antennas. The antennas share the same short pin with the width between at least two antennas of the plurality of antennas designed to minimize coupling when the at least two antennas operate at a same frequency. The short pin width is at least λ/8 where λ is based on a lowest frequency of operation of the antenna system, the lowest frequency of operation is about 2.4 GHz. The common short pin also includes a minimum distance to the associated antenna feed. Where the different short pins are located together the antenna includes a first short pin as a cylinder and a second short pin located within the cylinder without contact therebetween.
1 . An antenna system comprising:
a plurality of antennas, each being one of an inverted-F antenna (IFA) type or a planar inverted-F antenna (PIFA) type;
wherein each of the plurality of antennas are associated with at least one short pin positioned between at least a portion of the plurality of antennas to minimize antenna separation between the plurality of antennas, the plurality of antennas share a same short pin, the same short pin being a planar conductive structure having a width of at least λ/8 and extending along a length between two or more of the plurality of antennas, where λ is based on a lowest frequency of operation of the antenna system, the planar conductive structure being configured to act as a distributed impedance element to reduce mutual coupling between the plurality of antennas while enabling an antenna-to-antenna spacing less than λ/20, wherein the width of at least λ/8 is selected based on the lowest frequency of operation of the antenna system such that the planar conductive structure provides distributed impedance that reduces mutual coupling between the plurality of antennas sharing the same short pin.
2 . The antenna system of claim 1 , wherein the same short pin has a width between at least two antennas of the plurality of antennas such that the same short pin physically bridges the at least two antennas to reduce mutual coupling therebetween.
3 . The antenna system of claim 1 , wherein the lowest frequency of operation is about 2.4 GHz.
4 . The antenna system of claim 1 , wherein the same short pin includes a minimum distance to associated antenna feeds of the plurality of antennas.
5 . The antenna system of claim 4 , wherein the minimum distance is about at least λ/10 where λ is based on a lowest frequency of operation of the antenna system.
6 . The antenna system of claim 1 , wherein the same short pin has a width between at least two antennas and a minimum distance to associated antenna feeds of the plurality of antennas, such that the width and the minimum distance are based on λ that is based on a lowest frequency of operation of the antenna system.
7 . The antenna system of claim 6 , wherein the plurality of antennas are on a dielectric carrier and λ is adjusted based thereon.
8 . The antenna system of claim 7 , wherein the dielectric carrier is located on a heatsink of an electronic device.
9 . The antenna system of claim 1 , wherein the plurality of antennas include three antennas, A1, A2, and A3, each sharing the same short pin.
10 . The antenna system of claim 9 , wherein the same short pin has a width between A1, A2 and a minimum distance to associated antenna feeds of the plurality of antennas, such that the width and the minimum distance are based on λ that is based on a lowest frequency of operation of the antenna system.
11 . The antenna system of claim 1 , wherein the same short pin is grounded to one of a printed circuit board (PCB) ground and a heatsink via a screw.
12 . The antenna system of claim 1 , wherein the at least one short pin comprises different short pins located together, the different short pins include a first short pin as a cylinder and a second short pin located within the cylinder without contact therebetween.
13 . The antenna system of claim 12 , wherein the cylinder is a screw boss and the second short pin includes screw threads of a screw that does not connect to the screw boss.
14 . The antenna system of claim 1 , wherein the plurality of antennas support any of 2.4 GHz, 5 GHz, and 6 GHz operation, wherein the any of 2.4 GHz, 5 GHz, and 6 GHz operation is multiple input-multiple output (MIMO).
15 . The antenna system of claim 1 , wherein one or more of the plurality of antennas include effective lengths supporting two or more frequency bands.
16 . A method comprising:
providing a plurality of antennas, each being one of an inverted-F antenna (IFA) type or a planar inverted-F antenna (PIFA) type; and
providing at least one short pin for the plurality of antennas positioned between at least a portion of the plurality of antennas to minimize antenna separation between the plurality of antennas, the plurality of antennas share a same short pin, the same short pin being a planar conductive structure having a width of at least λ/8 and extending along a length between two or more of the plurality of antennas, where λ is based on a lowest frequency of operation of the plurality of antennas, the planar conductive structure being configured to act as a distributed impedance element to reduce mutual coupling between the plurality of antennas while enabling an antenna-to-antenna spacing less than λ/20, wherein the width of at least λ/8 is selected based on the lowest frequency of operation of the antenna system such that the planar conductive structure provides distributed impedance that reduces mutual coupling between the plurality of antennas sharing the same short pin.
17 . A compact electronic device comprising:
a compact housing;
circuitry in the compact housing; and
a plurality of antennas communicatively coupled to the circuitry, each being one of an inverted-F antenna (IFA) type or a planar inverted-F antenna (PIFA) type;
wherein each of the plurality of antennas are associated with at least one short pin positioned between at least a portion of the plurality of antennas to minimize antenna separation between the plurality of antennas in the compact housing, the plurality of antennas share a same short pin, the same short pin being a planar conductive structure having a width of at least λ/8 and extending along a length between two or more of the plurality of antennas, where λ is based on a lowest frequency of operation of the plurality of antennas, the planar conductive structure being configured to act as a distributed impedance element to reduce mutual coupling between the plurality of antennas while enabling an antenna-to-antenna spacing less than λ/20, wherein the width of at least K/8 is selected based on the lowest frequency of operation of the plurality of antennas such that the planar conductive structure provides distributed impedance that reduces mutual coupling between the plurality of antennas sharing the same short pin.
18 . The compact electronic device of claim 17 , further comprising the at least one short pin comprising a set of different short pins.