Pseudo-spectrum averaging for angle of arrival detection

Patent metadata

Field	Value
Publication number	US-11143735-B2
Application number	US-201816229105-A
Country	US
Kind code	B2
Filing date	Dec 21, 2018
Priority date	Dec 21, 2018
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

A system and method for determining a direction of arrival of an incoming signal is disclosed. The present system utilizes a plurality of pseudo-spectrums to create a more accurate result matrix. The pseudo-spectrums are one or two dimensional arrays, where peaks in the arrays are indicative of the angle of arrival. A result matrix is generated by performing a mathematical operation of corresponding elements in each pseudo-spectrum. This mathematical operation may be addition or multiplication. The result matrix provides a more accurate indication of the angle of arrival than can otherwise by achieved. In some embodiments, a measure of quality may also be calculated for the result matrix.

First claim

What is claimed is:

1. A method of improving the accuracy of an angle of arrival or an angle of departure algorithm, wherein the algorithm is used to determine an angle of arrival or angle of departure of radio frequency signals, comprising:
executing the angle of arrival or angle of departure algorithm a plurality of times so as to create a plurality of pseudo-spectrums, wherein the pseudo-spectrums comprise one or two dimensional arrays;
performing a mathematical operation on the plurality of pseudo-spectrums to produce a result matrix; and
determining the angle of arrival or angle of departure of the radio frequency signals based on the result matrix, wherein the mathematical operation improves the accuracy of the angle of arrival or angle of departure algorithm.

2. The method of claim 1 , wherein the mathematical operation comprises adding corresponding elements from each of the plurality of pseudo-spectrums to form the result matrix.

3. The method of claim 2 , further comprising determining a measure of quality.

4. The method of claim 3 , further comprising:
normalizing the result matrix by dividing each element in the result matrix by the largest value contained in the result matrix to form a normalized result matrix; and
adding all of the elements of the normalized result matrix together to generate an integral;
wherein the integral is indicative of the accuracy of the angle of arrival or angle of departure algorithm.

5. The method of claim 1 , wherein the mathematical operation comprises multiplying corresponding elements from each of the plurality of pseudo-spectrums to form the result matrix.

6. The method of claim 1 , wherein the plurality of pseudo-spectrums are created based on incoming radio frequency signals acquired at a plurality of different frequencies.

7. The method of claim 6 , wherein the incoming radio frequency signals comprise a plurality of beacons, and a transmitter sends the plurality of beacons using a frequency hopping technique.

8. The method of claim 1 , wherein the angle of arrival or angle of departure is used to perform wayfinding.

9. The method of claim 1 , wherein the angle of arrival or angle of departure is used to perform spatial positioning.

10. The method of claim 1 , wherein the angle of arrival or angle of departure algorithm continuously generates pseudo-spectrums and the result matrix is generated using a rolling average.

11. A locator device, comprising:
a one or two dimensional antenna array;
a wireless receiver in communication with the antenna array;
a processing unit; and
a memory device in communication with the processing unit, further comprising instructions, which when executed by the processing unit, enable the locator device to:
generate a plurality of pseudo-spectrums based on incoming signals received by the wireless receiver, using an angle of arrival algorithm;
perform a mathematical operation on the plurality of pseudo-spectrums to create a result matrix; and
determine an angle of arrival from the result matrix, wherein the mathematical operation improves the accuracy of the angle of arrival algorithm.

12. The locator device of claim 11 , wherein the mathematical operation comprises adding corresponding elements from each of the plurality of pseudo-spectrums to form the result matrix.

13. The locator device of claim 12 , further comprising determining a measure of quality.

14. The locator device of claim 13 , further comprising instructions, which when executed by the processing unit, enable the locator device to:
normalize the result matrix by dividing each element in the result matrix by the largest value contained in the result matrix to form a normalized result matrix; and
add all of the elements of the normalized result matrix together to generate an integral;
wherein the integral is indicative of the accuracy of the angle of arrival algorithm.

15. The locator device of claim 11 , wherein the mathematical operation comprises multiplying corresponding elements from each of the plurality of pseudo-spectrums to form the result matrix.

16. The locator device of claim 11 , wherein the plurality of pseudo-spectrums are generated based on incoming signals acquired at a plurality of different frequencies.

17. The locator device of claim 11 , further comprising an indicator to inform an operator of the angle of arrival.

18. A device, comprising:
an antenna;
a wireless receiver in communication with the antenna;
a processing unit; and
a memory device in communication with the processing unit, further comprising instructions, which when executed by the processing unit, enable the device to:
generate a plurality of pseudo-spectrums based on incoming signals received by the wireless receiver, using an angle of departure algorithm;
perform a mathematical operation on the plurality of pseudo-spectrums to create a result matrix; and
determine an angle of departure from the result matrix, wherein the mathematical operation improves the accuracy of the angle of departure algorithm.

19. The device of claim 18 , further comprising an indicator to inform an operator of the angle of departure.

20. The device of claim 18 , further comprising an indicator to inform an operator of its spatial position.

Assignees

• Silicon Lab Inc

Inventors

• Lehtimaki Sauli Johannes

Classifications

• G01S5/0063

  of measured values, i.e. measurement on base station and position calculation on mobile · CPC title

• H04B1/7156

  Arrangements for sequence synchronisation · CPC title

• 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

• H04B7/0897

  using beamforming per multi-path, e.g. to cope with different directions of arrival [DOA] at different multi-paths · CPC title

• G01S5/04

  Position of source determined by a plurality of spaced direction-finders · CPC title