AOA determination method and associated wireless communication device and radio base station

Patent metadata

Field	Value
Publication number	US-10877126-B2
Application number	US-201515546385-A
Country	US
Kind code	B2
Filing date	Jan 30, 2015
Priority date	Jan 30, 2015
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

The present disclosure provides a method implemented in a wireless communication device for determining an Angle of Arrival (AOA) of a wireless signal received at the wireless communication device. The method comprises estimating the AOA of the wireless signal, determining that the estimated AOA is ambiguous and acquiring signal strength measurements for the wireless signal received at two other wireless communication devices, which are located substantively symmetrically about a normal of the wireless communication device's antenna array. The method further comprises disambiguating the estimated AOA based on a comparison of the acquired signal strength measurements. The present disclosure also provides the wireless communication device as well as a Radio Base Station (RBS) comprising the wireless communication device.

First claim

What is claimed is:

1. A wireless communication device for determining an Angle of Arrival (AOA) of a wireless signal received at the wireless communication device, the wireless communication device comprising one or more processors configured to:
estimate the AOA of the wireless signal;
determine that the estimated AOA is ambiguous based on determining a credible AOA range, wherein the credible AOA range is defined such that no AOA in the credible AOA range has a mirrored AOA and no mirrored AOA of an AOA appears in the credible AOA range, and determining that the estimated AOA is ambiguous when the estimated AOA falls outside the credible AOA range;
acquire signal strength measurements for the wireless signal received at two other wireless communication devices, which are located substantively symmetrically about a normal of an antenna array of the wireless communication device; and
disambiguate the estimated AOA based on a comparison of the acquired signal strength measurements.

2. The wireless communication device of claim 1 , wherein the credible AOA range is [−θ cred , θ cred ] where θ cred is the minimum one of arcsin (λ/2 d) and arcsin (−sin(θ max )+λ/d), λ denotes a wavelength of the wireless signal, d denotes a space between adjacent antenna elements of said wireless communication device's antenna array and θ max denotes a maximum possible AOA for the wireless communication device.

3. The wireless communication device of claim 1 , wherein the one or more processors are configured to
determine the AOA as the estimated AOA, when the comparison of the acquired signal strength measurements indicates that the wireless signal is from one side of the normal of said wireless communication device's antenna array while the sign of the estimated AOA indicates that the wireless signal is from the same side of the normal, and
determine the AOA as a mirrored AOA of the estimated AOA, when the comparison of the acquired signal strength measurements indicates that the wireless signal is from one side of the normal of said wireless communication device's antenna array while the sign of the estimated AOA indicates that the wireless signal is from the other side of the normal.

4. The wireless communication device of claim 3 , wherein the mirrored AOA of the estimated AOA is determined according to the following:

{

θ
=

arcsin
⁡

(

sin
⁡

(

θ
est

)

+

λ
d

)

,

θ
est

<
0

θ
=

arcsin
⁡

(

sin
⁡

(

θ
est

)

-

λ
d

)

,

θ
est

>
0

,

where θ denotes the mirrored AOA, θ est denotes the estimated AOA, λ denotes a wavelength of the wireless signal and d denotes a space between adjacent antenna elements of said wireless communication device's antenna array.

5. The wireless communication device of claim 3 , wherein
when the signal strength measurement for the wireless signal received at one of said two other wireless communication devices is higher than the signal strength measurement for the wireless signal received at the other of said two other wireless communication devices, the comparison of the acquired signal strength measurements indicates that the wireless signal is from one side of the normal at which said one of said two other wireless communication devices is located.

6. The wireless communication device of claim 1 , wherein said wireless communication device and said two other wireless communication devices respectively correspond to three sectors of a Radio Base Station (RBS) and the sectors corresponding to said two other wireless communications are respectively adjacent to the sector corresponding to said wireless communication device.

7. The wireless communication device of claim 1 , wherein said antenna array is a Uniform Linear Array (ULA).

8. A Radio Base Station (RBS), comprising the wireless communication device according to claim 1 .

Assignees

• Ericsson Telefon Ab L M

Inventors

• Zhang Yipeng
• Cui Wenming
• Zhu Huaisong

Classifications

• G01S3/46 Primary

  using antennas spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems · CPC title

• G01S3/28 Primary

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