High-resolution, accurate, two-dimensional direction-of-arrival estimation method based on coarray tensor spatial spectrum searching with co-prime planar array

Patent metadata

Field	Value
Publication number	US-2021364591-A1
Application number	US-202117395478-A
Country	US
Kind code	A1
Filing date	Aug 6, 2021
Priority date	May 3, 2020
Publication date	Nov 25, 2021
Grant date	—

Abstract

Disclosed is a high-resolution accurate two-dimensional direction-of-arrival estimation method based on coarray tensor spatial spectrum searching with coprime planar array, which solves the problem of multi-dimensional signal loss and limited spatial spectrum resolution and accuracy in existing methods. The implementation steps are: constructing a coprime planar array; tensor signal modeling for the coprime planar array; deriving coarray statistics based on coprime planar array cross-correlation tensor; constructing the equivalent signals of a virtual uniform array; deriving a spatially smoothed fourth-order auto-correlation coarray tensor; realizing signal and noise subspace classification through coarray tensor feature extraction; performing high-resolution accurate two-dimensional direction-of-arrival estimation based on coarray tensor spatial spectrum searching. In the present method, multi-dimensional feature extraction based on coarray tensor statistics for coprime planar array is used to implement high-resolution, accurate two-dimensional direction-of-arrival estimation based on tensor spatial spectrum searching, and the method can be used for passive detection and target positioning.

First claim

What is claimed is:

1 . A high-resolution accurate two-dimensional direction-of-arrival estimation method based on coarray tensor spatial spectrum searching with coprime planar array, comprising the following steps of:
(1) constructing, by a receiving end, an architecture using 4M x M y +N x N y −1 physical antenna sensors according to a structure of the coprime planar array, wherein M x , N x and M y , N y are respectively a pair of prime integers, and M x <N x , M y <N y ; and the coprime planar array can be decomposed into two sparse uniform subarrays 1 and 2 ; (2) assuming that there are K far-field narrowband incoherent sources from directions of {(θ 1 , φ 1 ), (θ 2 , φ 2 ), . . . (θ K , φ K )}, then the received signal of the sparse subarray 1 of the coprime planar array being expressed by a three-dimensional tensor X 1 ∈ 2M x ×2M y ×L (L is the number of snapshots) as:

x
1

=

∑

k
=
1

K

⁢

a

M
⁢
x

⁡

(

θ
k

,

φ
k

)

∘

a
My

⁡

(

θ
k

,

φ
k

)

∘

s
k

+

𝒩
1

,

where s k =[s k,1 , s k,2 , . . . , s k,L ] T is a multi-snapshot sampling signal waveform corresponding to the k th incident source, [⋅] T represents transposition operation, ∘ represents a vector outer product, 1 is a noise tensor independent of each source, a Mx (θ k , φ k ) and a My (θ k , φ k ) are respectively steering vectors of 1 in x-axis and y-axis directions, corresponding to the k th source with a direction-of-arrival of (θ k , φ k ), which are expressed as:

a
Mx

⁡

(

θ
k

,

φ
k

)

=

[

1
,

e

-
j

⁢

⁢
π
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1

(
2
)

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sin
⁡

(

φ
k

)

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cos
⁡

(

θ
k

)

,
…
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,

e

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π
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1

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sin
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cos
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(

Assignees

• Univ Zhejiang

Inventors

• Zhou Chengwei
• Zheng Hang
• Chen Jiming
• Shi Zhiguo

Classifications

• H01Q21/061

  Two dimensional planar arrays · CPC title

• G01S3/74 Primary

  Multi-channel systems specially adapted for direction-finding, i.e. having a single antenna system capable of giving simultaneous indications of the directions of different signals (systems in which the directions of different signals are determined sequentially and displayed simultaneously G01S3/04, G01S3/14) · CPC title

• G01S3/46

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

• G01S3/043

  Receivers · CPC title

• G01S3/023

  Monitoring or calibrating · CPC title