In this study, the three-dimensional Cartesian acoustic parabolic equation is fully solved in the stair-step representation of an ocean environment based on the split-step Padé algorithm. The sum representation of the Padé approximation of a full exponential operator in the split-step marching solution is used for parallel computing. A stabilized self-starter solution is derived in the same way. This solver is benchmarked against reference solutions for a rectangular duct propagation, an ideal wedge problem, and an axisymmetric ocean. Additionally, a solution for the Gaussian canyon problem is provided and compared with that obtained from the approximate parabolic equation solver, considering a leading-order cross-term.

1.
D. B.
Kirk
and
W. W.
Hwu
,
Programming Massively Parallel Processors: A Hands-on Approach
, 3rd ed. (
Elsevier
,
New York
,
2017
), Chap. 1.
2.
M. D.
Collins
, “
Generalization of the split-step Padé solution
,”
J. Acoust. Soc. Am.
96
,
382
385
(
1994
).
3.
M. D.
Collins
, “
A split-step Padé for the parabolic equation method
,”
J. Acoust. Soc. Am.
93
,
1736
1742
(
1993
).
4.
M. D.
Collins
and
S. A.
Chin-Bing
, “
A three-dimensional parabolic equation model that includes the effects of rough boundaries
,”
J. Acoust. Soc. Am.
87
,
1104
1109
(
1990
).
5.
D.
Lee
,
G.
Botseas
, and
W. L.
Siegmann
, “
Examination of three-dimensional effects using a propagation model with azimuth-coupling capacity (FOR3D)
,”
J. Acoust. Soc. Am.
91
,
3192
3202
(
1992
).
6.
J. A.
Fawcett
, “
Modeling three-dimensional propagation in an ocean wedge using parabolic equation methods
,”
J. Acoust. Soc. Am.
93
,
2627
2632
(
1993
).
7.
K. B.
Smith
, “
A three-dimensional propagation algorithm using finite azimuthal aperture
,”
J. Acoust. Soc. Am.
106
,
3231
3239
(
1999
).
8.
G. H.
Brooke
,
D. J.
Thomson
, and
G. R.
Ebbeson
, “
PECAN: A Canadian parabolic equation model for underwater sound propagation
,”
J. Comput. Acoust.
9
,
69
100
(
2001
).
9.
F.
Sturm
and
J. A.
Fawcett
, “
On the use of higher-order azimuthal schemes in 3-D PE modeling
,”
J. Acoust. Soc. Am.
113
,
3134
3145
(
2003
).
10.
F.
Sturm
, “
Numerical study of broadband sound pulse propagation in three-dimensional oceanic waveguides
,”
J. Acoust. Soc. Am.
117
,
1058
1079
(
2005
).
11.
L.
Hsieh
,
C.
Chen
,
M.
Yuan
, and
Y.
Lin
, “
Azimuthal limitation in 3D PE approximation for underwater acoustic propagation
,”
J. Comput. Acoust.
15
,
221
233
(
2007
).
12.
Y.
Lin
and
T. F.
Duda
, “
A higher-order split-step Fourier parabolic-equation sound propagation solution scheme
,”
J. Acoust. Soc. Am.
132
,
EL61
EL67
(
2012
).
13.
Y.
Lin
,
J. M.
Collis
, and
T. F.
Duda
, “
A three-dimensional parabolic equation model of sound propagation using higher-order operator splitting and Padé approximations
,”
J. Acoust. Soc. Am.
132
,
EL364
EL370
(
2012
).
14.
Y.
Lin
,
T. F.
Duda
, and
A. E.
Newhall
, “
Three-dimensional sound propagation models using the parabolic-equation approximation and the split-step Fourier method
,”
J. Comput. Acoust.
21
,
1250018
(
2013
).
15.
F.
Sturm
, “
Leading-order cross term correction of three-dimensional parabolic equation models
,”
J. Acoust. Soc. Am.
139
,
263
270
(
2016
).
16.
C.
Xu
,
J.
Tang
,
S.
Piao
,
J.
Liu
, and
S.
Zhang
, “
Developments of parabolic equation method in the period of 2000–2016
,”
Chin. Phys. B
25
,
124315
(
2016
).
17.
M. F.
Levy
and
A. A.
Zaporozhets
, “
Target scattering calculations with the parabolic equation method
,”
J. Acoust. Soc. Am.
103
,
735
741
(
1998
).
18.
K.
Lee
and
W.
Seong
, “
Full 3D one-way parabolic equation algorithm
,”
J. Acoust. Soc. Kr.
25
,
67
68
(
2006
) (in Korean).
19.
J. M.
Collis
, “
Three-dimensional underwater sound propagation using a split-step Padé parabolic equation solution
,”
J. Acoust. Soc. Am.
130
,
2528
(
2011
).
20.
K.
Lee
and
W.
Seong
, “
The perfectly matched layer applied to the split-step Padé PE solver in an ocean waveguide
,”
J. Acoust. Soc. Kr.
25
,
131
135
(
2006
).
21.
M.
Levy
,
Parabolic Equation Methods for Electromagnetic Wave Propagation
(
The IEE
,
London
,
2011
), Chap. 8.3.
22.
M. D.
Collins
, “
Higher-order Padé approximations for accurate and stable elastic parabolic equations with application to interface wave propagation
,”
J. Acoust. Soc. Am.
89
,
1050
1057
(
1991
).
23.
R. J.
Cederberg
and
M. D.
Collins
Application of an improved self-starter to geoacoustic inversion
,”
IEEE J. Ocean. Eng.
22
,
102
109
(
1997
).
24.
M. D.
Collins
, “
A self-starter for the parabolic equation method
,”
J. Acoust. Soc. Am.
92
,
2069
2074
(
1992
).
25.
M. D.
Collins
, “
The stabilized self-starter
,”
J. Acoust. Soc. Am.
106
,
1724
1726
(
1999
).
26.
F. A.
Milinazzo
,
C. A.
Zala
, and
G. H.
Brooke
, “
Rational square-root approximations for parabolic equation algorithms
,”
J. Acoust. Soc. Am.
101
,
760
766
(
1997
).
27.
T.
Kim
, “Numerical observation of the statistics of acoustic wave propagation through a shallow water environment
,” M.S. thesis,
Seoul National University
, Seoul,
2003
.
28.
H. D.
Geiger
and
P. F.
Daley
, “
Finite difference modelling of the full acoustic wave equation in Matlab
,”
CREWES Res. Rep.
15
,
1
9
(
2003
).
29.
MathWorks
,
Parallel Computing Toolbox: User's Guide
(
The MathWorks, Inc.
,
MA
,
2018
).
30.
F. B.
Jensen
,
W. A.
Kuperman
,
M. B.
Porter
, and
H.
Schmidt
,
Computational Ocean Acoustics
, 2nd ed. (
Springer
,
New York
,
2011
), Chap. 6.
31.
G. B.
Deane
and
M. J.
Buckingham
, “
An analysis of the three-dimensional sound field in a penetrable wedge with a stratified fluid or elastic basement
,”
J. Acoust. Soc. Am.
93
,
1319
1328
(
1993
).
32.
J.
Tang
,
P. S.
Petrov
,
S.
Piao
, and
S. B.
Kozitskiy
, “
On the method of source images for the wedge problem solution in ocean acoustics: Some corrections and appendices
,”
Acoust. Phys.
64
,
225
236
(
2018
).
33.
A.
Tolstoy
,
K. B.
Smith
, and
N.
Maltsev
, “
The SWAM'99 workshop—An overview
,”
J. Comput. Acoust.
9
,
1
16
(
2001
).
34.
K.
Lee
,
W.
Seong
, and
Y.
Na
, “
Three-dimensional Cartesian parabolic equation model with higher order cross-terms using operator splitting, rational filtering, and split-step Padé algorithm
,”
J. Acoust. Soc. Am.
146
(
3
),
2041
2049
(
2019
).
35.
M. D.
Collins
, “
User's guide for RAM versions 1.0 and 1.0p
,” Technical report, Naval Research Laboratory, Washington, D.C.
36.
M. D.
Collins
and
W. A.
Westwood
, “
A higher-order energy-conserving parabolic equation for range-dependent ocean depth, sound speed, and density
,”
J. Acoust. Soc. Am.
89
,
1068
1075
(
1991
).
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