Device and method for unambiguous determination of angle of arrival for RF signals

Patent metadata

Field	Value
Publication number	US-11442131-B2
Application number	US-201916579968-A
Country	US
Kind code	B2
Filing date	Sep 24, 2019
Priority date	Oct 15, 2018
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

There is described a device for determining an angle of arrival of a received RF signal, the device comprising (a) a first antenna and a second antenna arranged with a predetermined distance between them on an antenna axis, the first antenna having a larger gain than the second antenna for directions corresponding to one side of the antenna axis, the second antenna having a larger gain than the first antenna for directions corresponding to the other side of the antenna axis, (b) receiver circuitry coupled to the first antenna and to the second antenna, the receiver circuitry being configured to determine a first phase and a first signal strength of a signal received by the first antenna and to determine a second phase and a second signal strength of a signal received by the second antenna, and (c) angle determining circuitry configured to determine the angle of arrival based on the first phase, the second phase, the first signal strength, and the second signal strength. There is also described a corresponding method, a computer program, and a computer program product.

First claim

The invention claimed is:

1. A device for determining an angle of arrival of a received RF signal, the device comprising:
a first antenna and a second antenna arranged with a predetermined distance between them on an antenna axis, the first antenna having a larger gain than the second antenna for directions corresponding to one side of the antenna axis, the second antenna having a larger gain than the first antenna for directions corresponding to the other side of the antenna axis;
receiver circuitry coupled to the first antenna and to the second antenna, the receiver circuitry being configured to determine a first phase and a first signal strength of a signal received by the first antenna and to determine a second phase and a second signal strength of a signal received by the second antenna;
angle determining circuitry configured to determine the angle of arrival based on the first phase, the second phase, the first signal strength, and the second signal strength;
wherein the first antenna is a directional antenna having a first gain for directions corresponding to the one side of the antenna axis and a second gain for directions corresponding to the other side of the antenna axis, the first gain being larger than the second gain; and
wherein the second antenna is an omnidirectional antenna having a gain that is less than the first gain of the first antenna and greater than the second gain of the first antenna.

2. The device according to claim 1 , wherein the angle determining circuitry is configured to determine a value of the angle of arrival based on a difference between the first phase and the second phase and to determine whether the signal is received from the one side or from the other side of the antenna axis based on a difference between the first signal strength and the second signal strength.

3. The device according to claim 1 , wherein;
the first gain for directions corresponding to the one side of the antenna axis corresponds to an angle of arrival between 0 and 180 degrees; and
the second gain for directions corresponding to the other side of the antenna axis corresponds to an angle of arrival between 180 and 360 degrees.

4. The device according to claim 1 , wherein the gain of the omnidirectional is the same for directions corresponding to the one side of the antenna axis and for directions corresponding to the other side of the antenna axis.

5. The device according to claim 1 , wherein the gain of the omnidirectional antenna corresponds to a numerical gain value.

6. The device according to claim 5 , wherein the numerical gain value is zero decibels (dB).

7. A method of determining an angle of arrival of a received RF signal, the method comprising:
receiving a signal at a first antenna and at a second antenna, the first antenna and the second antenna being arranged with a predetermined distance between them on an antenna axis, the first antenna having a larger gain than the second antenna for directions corresponding to one side of the antenna axis, the second antenna having a larger gain than the first antenna for directions corresponding to the other side of the antenna axis;
determining a first phase and a first signal strength of the signal received by the first antenna;
determining a second phase and a second signal strength of the signal received by the second antenna;
determining the angle of arrival based on the first phase, the second phase, the first signal strength, and the second signal strength;
wherein the first antenna is a directional antenna having a first gain for directions corresponding to the one side of the antenna axis and a second gain for directions corresponding to the other side of the antenna axis, the first gain being larger than the second gain; and
wherein the second antenna is an omnidirectional antenna having a gain that is less than the first gain of the first antenna and greater than the second gain of the first antenna.

8. A computer program comprising computer executable instructions which, when executed by a computer, causes the computer to perform the steps of the method according to claim 7 .

9. A computer program product comprising a computer readable data carrier loaded with a computer program according to claim 8 .

Assignees

• Nxp Bv

Inventors

• Al-Kadi Ghiath
• Muehlmann Ulrich Andreas
• Schober Michael

Classifications

• G01S3/30

  derived directly from separate directional systems · CPC title

• G01S3/28

  using amplitude comparison of signals derived simultaneously from receiving antennas or antenna systems having differently-oriented directivity characteristics · CPC title

• G01S3/38

  using adjustment of real or effective orientation of directivity characteristic of an antenna or an antenna system to give a desired condition of signal derived from that antenna or antenna system, e.g. to give a maximum or minimum signal (G01S3/16, G01S3/28 take precedence) · 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