Loop booster for small IoT devices
A wireless device operates in at least one frequency region and/or frequency band and comprises a radiating system that includes a radiating structure comprising a ground plane layer having a clearance area at a corner of a ground plane rectangle that encompasses the ground plane layer, an antenna element located in the clearance area, and two connections of the antenna element to the ground plane layer. The radiating system further comprises a radiofrequency system comprising a matching network and/or an electronic circuit. One of the antenna element to ground plane layer connections is connected to an input/output port of the radiating system and a second connection connects the antenna element to the ground plane layer through a short-circuit or an electronic circuit.
1 . A wireless device comprising:
a radiating system that comprises:
a radiating structure including:
a ground plane layer having a clearance area at a corner of a ground plane rectangle, the ground plane rectangle being the minimum-sized rectangle that encompasses the ground plane layer;
an antenna element located in the clearance area; and
first and second connections of the antenna element to the ground plane layer, wherein the first and second connections are at opposite corners of the clearance area;
a radiofrequency system including a matching network; and
an input/output port, wherein the first connection is connected to the matching network and to the input/output port, and the second connection is a non-driven port with an inductive input impedance.
2 . The wireless device of claim 1 , wherein the antenna element comprises a radiation booster.
3 . The wireless device of claim 1 , wherein the antenna element comprises an electrically-small antenna.
4 . The wireless device of claim 1 , wherein the non-driven port is connected to an electronic circuit that comprises a circuit component.
5 . The wireless device of claim 4 , wherein the circuit component comprises a passive component.
6 . The wireless device of claim 4 , wherein the circuit component comprises an active component.
7 . The wireless device of claim 1 , wherein the non-driven port is connected to a short-circuit.
8 . The wireless device of claim 1 , wherein the matching network comprises a series capacitor at a beginning of the matching network.
9 . The wireless device of claim 1 , wherein the matching network comprises first and second series capacitors at a beginning of the matching network.
10 . The wireless device of claim 9 , wherein the matching network further comprises a parallel capacitor at an end of the matching network.
11 . A wireless device comprising:
a radiating system operable in a first frequency region of operation from 400 MHz to 401 MHz, the radiating system comprising:
a radiating structure including:
a ground plane layer having a clearance area at a corner of a ground plane rectangle, the ground plane rectangle being the minimum-sized rectangle that encompasses the ground plane layer of the radiating structure, the ground plane layer having a length and a width smaller than 0.3 times a free-space wavelength corresponding to a lowest frequency of the first frequency region of operation;
an antenna element located in the clearance area and arranged substantially along an edge; and
first and second connections of the antenna element to the ground plane layer, wherein the first and second connections are at opposite corners of the clearance area;
a radiofrequency system comprising a matching network; and
an input/output port, wherein the first connection is connected to the matching network and to the input/output port, and the second connection is a non-driven port with an inductive input impedance and is connected to a short-circuit.
12 . The wireless device of claim 11 , wherein the antenna element comprises a radiation booster.
13 . The wireless device of claim 11 , wherein the antenna element comprises an electrically-small antenna.
14 . The wireless device of claim 11 , wherein the ground plane layer has a length and a width smaller than 0.2 times the free-space wavelength corresponding to the lowest frequency of the first frequency region of operation.
15 . The wireless device of claim 11 , wherein the ground plane layer has a length and a width smaller than 0.1 times the free-space wavelength corresponding to the lowest frequency of the first frequency region of operation.
16 . The wireless device of claim 11 , wherein the matching network comprises a series capacitor at a beginning of the matching network.
17 . The wireless device of claim 11 , wherein the matching network comprises first and second series capacitors at a beginning of the matching network.
18 . The wireless device of claim 17 , wherein the matching network further comprises a parallel capacitor at an end of the matching network.