Minimize Stripmap

Stripmap (SM) mode acquires data with an 80 km swath at slightly better than 5 m by 5 m spatial resolution (single look). The ground swath is illuminated by a continuous sequence of pulses while the antenna beam is pointing to a fixed azimuth angle and an approximately fixed off-nadir angle (this is subject to small variations because of roll steering). SM images have continuous along track image quality at an approximately constant incidence angle.

The following table shows the main characteristics of Stripmap mode.

Characteristic Value
Swath width 80 km
Incidence angle range 18.3° - 46.8°
Elevation beams 6
Polarisation options Dual HH+HV, VV+VH
Single HH, VV
Maximum Noise Equivalent Sigma Zero (NESZ) -22 dB

Table 1: Characteristics of Stripmap mode

Stripmap imaging mode operates with one of six predefined elevation beams, each at a different incidence angle. The table below shows the incidence and off-nadir angles for Stripmap beams.

The incidence angle is the angle between the incident SAR beam and the axis perpendicular to the local geodetic ground surface.

The off-nadir angle is the look angle between the satellite's nadir position and the SAR beam.

Beam S1 S2 S3 S4 S5 S6
Off-nadir angles at
min orbit altitude [°]
17.93-23.53 21.00-26.33 26.18-30.99 30.87-35.15 35.07-38.85 37.53-41.01
Incident angles at min
orbit altitude [°]
19.99-26.31 23.45-29.50 29.33-34.85 34.71-39.72 39.62-44.12 42.53-46.73
Off-nadir angles at
max orbit altitude [°]
16.45-21.96 19.51-24.77 24.67-29.45 29.34-33.63 33.53-37.34 35.98-39.51
Incident angles at max
orbit altitude [°]
18.32-24.55 21.78-27.76 27.64-33.13 33.00-38.02 37.89-42.43 40.79-45.04

Table 2: Angles for Stripmap mode beams

Stripmap mode is used to image small islands and in exceptional cases only, to support emergency management actions.