Electronic device having angle of arrival detection capabilities

Patent metadata

Field	Value
Publication number	US-11095017-B2
Application number	US-201816035325-A
Country	US
Kind code	B2
Filing date	Jul 13, 2018
Priority date	Jul 13, 2018
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

An electronic device may be provided with wireless circuitry that includes first, second, and third antennas used to determine the position and orientation of the electronic device relative to external equipment. The antennas may include patch elements on respective substrates mounted to a flexible printed circuit. Each substrate may include fences of conductive vias that are coupled to ground and that laterally surround the corresponding patch element. Control circuitry may identify phase differences between the first and second antennas and between the second and third antennas and may identify an angle of arrival of received ultra-wideband signals using the phase differences. The control circuitry may compare the phase differences to a set of predetermined surfaces of phase differences to identify environmental loading conditions for the antenna. The control circuitry may correct the angle of arrival using offsets identified based on the environmental loading conditions.

First claim

What is claimed is:

1. Apparatus comprising:
a first substrate;
a second substrate mounted to the first substrate;
a patch antenna having an antenna resonating element formed from a conductive trace on the second substrate, wherein the patch antenna is configured to receive radio-frequency signals in an ultra-wideband communications band;
a ground trace in the second substrate;
a radio-frequency transmission line in the first substrate and having a signal conductor coupled to the conductive trace by a conductive feed via that extends through the second substrate and through an opening in the ground trace; and
a fence of conductive vias, wherein the fence of conductive vias is coupled to the ground trace, extends through the second substrate, and laterally surrounds the conductive feed via.

2. The apparatus defined in claim 1 , wherein the conductive trace is formed on a surface of the second substrate and the fences of conductive vias extend from the ground trace to conductive pads on the surface of the substrate.

3. The apparatus defined in claim 2 , wherein the conductive pads are laterally separated from the conductive trace at the surface of the second substrate by a distance, the distance being between 0.4 mm and 0.6 mm.

4. The apparatus defined in claim 1 , wherein the first substrate comprises a flexible printed circuit and the second substrate comprises a material selected from the group consisting of: polyimide, liquid crystal polymer, and plastic.

5. The apparatus defined in claim 1 , further comprising control circuitry configured to identify an angle of arrival of the radio-frequency signals received by the patch antenna.

6. The apparatus defined in claim 1 wherein the second substrate comprises ceramic.

7. The apparatus defined in claim 6 wherein the first substrate comprises a flexible printed circuit.

8. The apparatus defined in claim 1 further comprising:
a third substrate mounted to the first substrate;
an additional patch antenna having an additional antenna resonating element formed from an additional conductive trace on the third substrate, wherein the additional patch antenna is configured to receive the radio-frequency signals in the ultra-wideband communications band;
an additional ground trace in the third substrate; and
an additional radio-frequency transmission line in the first substrate and having an additional signal conductor coupled to the additional conductive trace by an additional conductive feed via that extends through the third substrate and through an additional opening in the additional ground trace.

9. The apparatus defined in claim 8 further comprising:
an additional fence of conductive vias, wherein the additional fence of conductive vias is coupled to the additional ground trace, extends through the third substrate, and laterally surrounds the additional conductive feed via.

10. The apparatus defined in claim 9 , further comprising:
a radio-frequency connector mounted to the first substrate, wherein the radio-frequency transmission line and the additional radio-frequency transmission line are coupled to the radio-frequency connector.

11. The apparatus defined in claim 8 , further comprising:
control circuitry configured to identify a phase difference between the patch antenna and the additional patch antenna based on the radio-frequency signals received by the patch antenna and the additional patch antenna, wherein the control circuitry is configured to determine an angle-of-arrival of the radio-frequency signals based on the identified phase difference.

12. The apparatus defined in claim 11 , wherein the control circuitry is configured to identify an operating environment for the patch antenna and the additional patch antenna based on the identified phase difference, the control circuitry is configured to select an offset value from a set of predetermined offset values based on the identified operating environment, and the control circuitry is configured to adjust the angle of arrival value using the selected offset value.

13. The apparatus defined in claim 8 , wherein the apparatus comprises an electronic device having opposing first and second faces and further comprises:
a display at the first face;
a dielectric layer at the second face; and
a conductive layer coupled to an interior surface of the dielectric layer, wherein the conductive layer comprises a first aperture that is aligned with the patch antenna and a second aperture that is aligned with the additional patch antenna.

14. The apparatus defined in claim 1 , further comprising:
a third substrate mounted to the first substrate
a fourth substrate mounted to the first substrate;
a first additional antenna having a first additional antenna resonating element formed from a first additional conductive trace on the third substrate, wherein the first additional antenna is configured to receive the radio-frequency signals in the ultra-wideband communications band; and
a second additional antenna having a second additional antenna resonating element formed from a second additional conductive trace on the fourth substrate, wherein the second additional antenna is configured to receive the radio-frequency signals in the ultra-wideband communications band.

15. The apparatus defined in claim 14 , further comprising:
a first additional ground trace in the third substrate;
a second additional ground trace in the fourth substrate;
a first additional radio-frequency transmission line in the first substrate and having a first additional signal conductor coupled to the first additional conductive trace by a first additional conductive feed via that extends through the third substrate and through a first additional opening in the first additional ground trace; and
a second additional radio-frequency transmission line in the first substrate and having a second additional signal conductor coupled to the second additional conductive trace by a second additional conductive feed via that extends through the fourth substrate and through a second additional opening in the second additional ground trace.

16. The apparatus defined in claim 15 , further comprising:
a first additional fence of conductive vias, wherein the first additional fence of conductive vias is coupled to the first additional ground trace, extends through the third substrate, and laterally surrounds the first additional conductive feed via; and
a second additional fence of conductive vias, wherein the second additional fence of conductive vias is coupled to the second additional ground trace, extends through the fourth substrate, and laterally surrounds the second additional conductive feed via.

17. The apparatus defined in claim 14 , further comprising control circuitry configured to:
identify a first phase difference between the patch antenna and the first additional antenna based on the radio-frequency signals received by the patch antenna and the first additional antenna;
identify a second phase difference between the first and second additional antennas based on the radio-frequency signals received by the first and second additional antennas; and
determine an angle of arrival value for the radio-frequency signals based on the first and second phase differences.

18. The apparatus defined in claim 17 , wherein the apparatus comprises an electronic device with opposing first and second faces, the apparatus further comprising:
a display at the first face;
a dielectric layer at the second face; and
a conductive layer coupled to an interior surface of the dielectr

Assignees

• Apple Inc

Inventors

• Cooper Aaron J
• Tayebi Amin
• Di Nallo Carlo
• Wang Zheyu

Classifications

• G01S3/48 Primary

  the waves arriving at the antennas being continuous or intermittent and the phase difference of signals derived therefrom being measured · CPC title

• H01Q21/065

  Patch antenna array · CPC title

• H01Q3/2605

  Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays · CPC title

• H01Q5/25

  Ultra-wideband [UWB] systems, e.g. multiple resonance systems; Pulse systems · CPC title

• G01S3/043

  Receivers · CPC title