INSSTACK

Description

INSSTACK generates velocities, displacements, or cumulative displacements for non-overlapping time steps corresponding to consecutive SAR acquisition times. INSSTACK supports line-of-sight measurements (LOS) from single stack output and geodetic (vertical, longitudinal (east/west)) from multi-stack output.

Parameters

Name	Type	Length	Value range
DUNITS	String	0 -	MM | CM | M | IN | FT Default: M
TUNITS	String	0 -	DAT | YEAR Default: YEAR

Parameter descriptions

DUNITS

The distance units used to measure the displacement.

TUNITS

The time units used to measure the time interval used for velocity estimates. This unit is also used as the X axis by the InSAR temporal chart tool.

Details

INSSTACK reads the stack of temporally ordered, non-overlapping displacements corresponding to each acquisition interval and converts them to velocity, displacement, or cumulative displacement in user defined units. For single stack input generated by INSDMV the output is written in the line-of-sight (LOS) direction. For multi-stack input generated by INSGEODISP, the output may be written in the vertical direction (up is positive) or the longitudinal direction (east is positive). If OQUANT is set to CDIS, the cumulative displacement for each layer is written. If OQUANT is set to AVER, the output will consist of a single layer of average velocity. The average velocity is calculated as the cumulative displacement divided by the reference stack time interval. The units selected for DUNITS and TUNITS are also used as the X and Y axis by the InSAR temporal chart tool.