Sparse optimization method based on cross-shaped three-dimensional imaging sonar array

Patent metadata

Field	Value
Publication number	US-2021190946-A1
Application number	US-201817056759-A
Country	US
Kind code	A1
Filing date	Oct 22, 2018
Priority date	Jun 14, 2018
Publication date	Jun 24, 2021
Grant date	—

Abstract

The present invention a sparse optimization method based on cross-shaped three-dimensional imaging sonar array, comprising the following steps: first, constructing a beam pattern simultaneously applicable to a near field and a far field based on a cross-shaped array; then, constructing an energy function required by sparse optimization according to the beam pattern; then, introducing an array element position disturbance into a simulated annealing algorithm to increase the degree of freedom of the sparse process and increase the sparse rate of the sparse array, and using the simulated annealing algorithm to sparse optimization of the energy function; finally, after optimization, a sparse optimization cross-shaped array is obtained. The present invention ensures that the three-dimensional imaging sonar system has the desired performance at any distance, and greatly reduces the hardware complexity of the system. It provides an effective method to achieve high performance and ultra-low complexity 3D imaging sonar system.

First claim

1 . A sparse optimization method based on cross-shaped three-dimensional imaging sonar array, comprising the following steps:
(1) constructing a beam pattern BP(W,u,v,δ,f j ) simultaneously applicable to a near field and a far field based on a cross-shaped array, the beam pattern BP(W,u,v,δ,f j ) being:

BP


(

W
,
u
,
v
,
δ
,

f
j

)

=



∑

n
=
0

N
-
1



ω
n

·

exp


[

-
j



2

π




f
j

c



y
n

·
v

+

δ


y
n
2

2

]



×



∑

m
=
1

M



ω
m



exp


[

-
j



2

π




f
j

c



x
m

·
u

+

δ


x
m
2

2

]



wherein, W is a weight coefficient of the array, including a weight coefficient ω n of the vertical transmitting array and a weight coefficient ω m of the horizontal receiving array;
f j is a transmitting frequency in the vertical beam j direction;
x m is a position of the m-th element of the horizontal receiving array;
y n is a position of the nth element of the vertical transmitting array;
c is a speed at which sound waves propagate in water;
δ=1/ r− 1/ r 0 ;

r is a target distance;
r 0 is a beam focusing distance;
u =sin β a −sin θ a ;

v =sin β e −sin θ e ;

β a is a horizontal beam arrival direction;
θ a is a horizontal beam focusing direction;
β e is a vertical beam arrival direction;
θ e is a vertical beam focusing direction;
when δ=0, BP is a far field beam pattern; when δ≠0, BP is a near field beam pattern;
(2) constructing an energy function E(W,A) required by sparse optimization according to the beam pattern BP(W,u,v,δ,f j ), the energy function E(W,A) being:

E


(

W
,
A

)

=

k
1



(

∫

δ

min

δ


Assignees

• Univ Zhejiang

Inventors

• Chen Yaowu
• Liu Xuesong
• Zhou Fan
• Jiang Rongxin
• Zhao Dongdong

Classifications

• G01S15/8993

  Three dimensional imaging systems · CPC title

• G01S15/8915 Primary

  using a transducer array · CPC title

• G01S7/6245

  Stereoscopic displays; Three-dimensional displays; Pseudo-three dimensional displays · CPC title

• G01S7/5205

  Means for monitoring or calibrating · CPC title

• G01S7/52004

  Means for monitoring or calibrating (short-range imaging G01S7/5205) · CPC title