Minimize Wave

SENTINEL-1 Wave mode is similar to ERS and ENVISAT wave mode imaging but with improved resolution, larger vignettes and a new 'leap frog' acquisition pattern. WV acquisitions consist of several vignettes exclusively in either VV or HH polarisation, with each vignette processed as a separate image. WV mode products can contain any number of vignettes, potentially amounting to an entire data-take. Each vignette will be contained in an independent image within the product.

Wave mode acquires data in 20 km by 20 km vignettes, at 5 m by 5 m spatial resolution, every 100 km along the orbit, acquired alternately on two different incidence angles. Vignettes on the same incidence angle are separated by 200 km. Swaths alternate incidence angles between near range and far range (23° and 36.5° respectively).

Figure 1: Alternating WV Mode Acquisitions

The Wave mode at VV polarisation is the default mode for acquiring data over open ocean. WV mode is acquired at the same bit rate as SM however, due to the small vignettes, single polarisation and sensing at 100 km intervals, the data volume is much lower. The table below shows the main characteristics of the Wave mode.

Characteristic Value
Vignette ground coverage 20 km
Along track distance between vignettes 100 km
Incidence angle ranges 21.6° - 25.1°
34.8° - 38.0°
Elevation beams 2
Azmiuth and range looks Single
Polarisation options Single HH, VV
Maximum Noise Equivalent Sigma Zero (NESZ) -22 dB
Radiometric stability 0.5 dB (3σ)
Radiometric accuracy 1 dB (3σ)
Phase error

Table 1: Characteristics of Wave mode

The table below shows the incidence and off-nadir angles for Wave mode beams.

Beam WV1 WV2
Off-nadir angles at
min orbit altitude
21.03-22.40 32.56-33.62
Incidence angles at
min orbit altitude
23.47-25.03 36.67-37.92
Off-nadir angles at
max orbit altitude
19.43-20.79 30.96-32.02
Incidence angles at
max orbit altitude
21.68-23.22 34.88-36.13

Table 2: Angles for Wave mode beams