The FIELDS
program uses the Green's functions calculated
by SCOOTER or SPARC and produces a shade file that contains a
sequence
of snapshots of the acoustic field as a function of range
and depth.
Files:
Name Unit Description
Input
*.FLP 1 FieLd Parameters
*.GRN 20 GReen's function
Output
*.PRT 6 PRinT file
*.SHD 25 SHaDe file
'RDB' ! 'R/X (coord), Lin/DB, Pos/Neg/Both'
200.0 220.0 501 ! RMIN, RMAX, NR
(1) - OPTIONS
Syntax:
OPT
Description:
OPT(1:1): Coordinates
'R' Cylindrical (R-Z) coordinates.
'X' Cartesian (X-Z) coordinates.
OPT(2:2): Spectrum
'P' Positive (recommended)
'N' Negative
'B' Both positive and negative
The spectral integral should formally be done from all along the real k-axis, however the negative portion contributes significantly only in the near-field. Run-time is less if it is neglected.
OPT(3:3): Interpolation type
'O' POlynomial (for broadband runs) (default)
'A' PAde (can produce better results for CW runs but is less reliable)
'*' Read in a source beam pattern file.
'O' Omnidirectional (default).
(2) - RECEIVER RANGES
Syntax: RMIN RMAX NR
Description:
RMIN: First receiver range (km)
RD: Last receiver range (km)
NR: Minimum number of receiver ranges
The actual number of ranges used is increased slightly to satisfy FFT sampling requirements.