Gamma MSP: Reference Manual

ERS_ENVISAT_proc

NAME
ERS_ENVISAT_proc - Updates the MSP sensor parameter and generates the processing parameter files from Level 0 (raw) ERS raw data in ENVISAT format. This program also reformats the raw SAR signal data to be compatible with the MSP. The entire level 0 data set is converted to 8-bit I/Q unsigned binary complex samples.

SYNOPSIS
ERS_ENVISAT_proc <L0> <SAR_par> <PROC_par> <raw> <ant_gain> [loff] [nl] [swst_flg]

L0 (input) Level 0 Image Mode ERS data file in Envisat format (SAR_IM__0P*.E*) SAR_par (input/output) MSP SAR sensor parameter file (ERS*_ESA.par) PROC_par (output) MSP processing parameter file, (example p.slc.par) raw (output) byte aligned 8-bit I/Q raw data loff number of lines offset from start of raw data file (enter - for default: 0) nl number of lines to extract (enter - for default: to end of input raw data swst_flg SWST data window position processing flag: 0: ignore changes in the data window position (only for corrupted data) 1: track changes in the data window position (default)

L0	(input) Level 0 Image Mode ERS data file in Envisat format (SAR_IM__0P.E)
SAR_par	(input/output) MSP SAR sensor parameter file (ERS*_ESA.par) that is located in the MSP sensors directory. Parameters for record length and headers will be adjusted.
PROC_par	(output) MSP processing parameter file, (example p.slc.par))
raw	(output) byte aligned 8-bit I/Q raw data
loff	offset lines to first line to extract (default = 0, enter - for default)
nl	number of lines to extract (default = to end of input, enter - for default)
swst_flg	SWST data window position processing flag: 0: ignore changes in the data window position (only for corrupted data) 1: track changes in the data window position (default)number of lines to extract (default = to end of input, enter - for default)

EXAMPLE
ERS_ENVISAT_proc ERS_ENVISAT_proc SAR_IM__0PXDLR19960203_130658_00000017G153_00281_23816_6033.E1 ERS1_ENVISAT.par p19960203.slc.par 19960203.raw

DESCRIPTION
ERS_ENVISAT_proc reads the ERS Level 0 data file in Envisat format and generates the MSP processing parameter (p*.slc.par) and updates the sensor parameter file along with reformatting the raw data. Level 0 files have names that begin with SAR_IM__0.... These files contain both raw data and meta data. Detailed information on the ERS raw data Level 0 in Envisat format is contaned in the Product Specification for ERS Products within ENVISAT Format available on-line at http://earth.esa.int.

The program now generates both the SAR sensor parameter file and MSP processing parameter file for the specific data set. In versions prior to 1.7, the user was required to enter a template MSP SAR sensor parameter file.

You also have the possibility to extract only a subset of the echoes from the raw data set. This is done by specifing the offset number of echoes to the first echo to extract loff, and the number of echoes to extract nl. This capability may be useful in the case of very large raw data sets.

To eliminate missing lines run ERS_fix with 'ENVISAT' for the ERS_PAF parameter on the raw data.

In some extreme case where all the range gate window position (SWST) data are corrupted, it is possible turn off checking and compensation of changes in the range gate (SWST) by setting the swst_flg to 0.