Apparatus for antenna impedance-matching and associated methods

Patent metadata

Field	Value
Publication number	US-11749893-B2
Application number	US-201916420111-A
Country	US
Kind code	B2
Filing date	May 22, 2019
Priority date	Aug 29, 2016
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

An apparatus includes a module, which includes an impedance matching circuit. The apparatus further includes a capacitor that is external to the module, and is coupled to the impedance matching circuit. The apparatus further includes a loop antenna to transmit or receive the RF signals. The loop antenna is coupled to the capacitor.

First claim

The invention claimed is:

1. An apparatus, comprising:
a module, comprising an impedance matching circuit;
a first capacitor external to the module and coupled to the impedance matching circuit; and
a loop antenna to transmit or receive the RF signals, wherein the loop antenna is coupled to the first capacitor,
wherein the first capacitor is coupled in series between the loop antenna and the impedance matching network.

2. The apparatus according to claim 1 , wherein the RF circuit transmits or receives RF signals.

3. The apparatus according to claim 2 , further comprising a second capacitor external to the module and coupled to the RF circuit and to the matching circuit.

4. The apparatus according to claim 1 , wherein a capacitance value of the first capacitor is tuned depending on a loop size of the loop antenna.

5. The apparatus according to claim 1 , wherein the impedance matching circuit comprises a resonant network coupled to a reactive network.

6. The apparatus according to claim 1 , wherein the impedance matching circuit comprises a first reactive network coupled to a second reactive network.

7. The apparatus according to claim 1 , wherein the loop antenna comprises a conductive loop of a substrate, and wherein the module and the first capacitor are attached to the substrate.

8. An apparatus, comprising:
a module, comprising:
a radio frequency (RF) circuit to transmit or receive RF signals; and
an impedance matching circuit;

a first capacitor external to the module and coupled to the impedance matching circuit;
a second capacitor external to the module, wherein the second capacitor is coupled to a the RF circuit; and
a loop antenna to transmit or receive the RF signals, wherein the loop antenna is coupled to the first capacitor,
wherein the first capacitor is coupled in series between the loop antenna and the impedance matching network.

9. The apparatus according to claim 8 , wherein a capacitance value of the first capacitor is tuned depending on a loop size of the loop antenna.

10. The apparatus according to claim 8 , wherein the loop antenna comprises a conductive loop of a substrate.

11. The apparatus according to claim 10 , wherein the module, the first capacitor, and the second capacitor are attached to the substrate.

12. The apparatus according to claim 8 , wherein impedance matching circuit comprises a resonant network coupled to a reactive network.

13. The apparatus according to claim 8 , wherein the impedance matching circuit comprises a first reactive network coupled to a second reactive network.

14. A method of fabricating an apparatus, the method comprising:
fabricating a module comprising an impedance matching circuit;
fabricating a first capacitor external to the module and coupled to the impedance matching circuit; and
fabricating a loop antenna to transmit or receive the RF signals, wherein the loop antenna is coupled to the first capacitor,
wherein the first capacitor is coupled in series between the loop antenna and the impedance matching network.

15. The method according to claim 14 , wherein fabricating the module comprises providing a radio frequency (RF) circuit to transmit or receive RF signals.

16. The method according to claim 15 , further comprising fabricating second capacitor external to the module and coupled to the RF circuit and to the matching circuit.

17. The method according to claim 14 , wherein a capacitance value of the first capacitor is tuned depending on a loop size of the loop antenna.

18. The method according to claim 14 , wherein the impedance matching circuit comprises a resonant network coupled to a reactive network.

19. The method according to claim 14 , wherein the impedance matching circuit comprises a first reactive network coupled to a second reactive network.

20. The method according to claim 14 , wherein the loop antenna comprises a conductive loop of a substrate, and wherein the module and the first capacitor are attached to the substrate.

Assignees

• Silicon Lab Inc

Inventors

• Voor Thomas E
• Zolomy Attila
• Rahikkala Pasi

Classifications

• H01Q7/005 Primary

  with variable reactance for tuning the antenna · CPC title

• H01Q1/2291

  used in Bluetooth® or Wi-Fi® devices of Wireless Local Area Networks [WLAN] (H01Q1/241 takes precedence; WLAN in general H04W) · CPC title

• H03H7/38

  Impedance-matching networks · CPC title

• H01Q7/00 Primary

  Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop · CPC title

• H03H7/40

  Automatic matching of load impedance to source impedance · CPC title