Mobile version

AltiKa, a dual-frequency radiometer

The radiometer onboard Saral is included in the AltiKa instrument since it shares the same antenna. It operates in dual-frequency (23.8 and 37 GHz) to correct altimetry measurements from wet troposphere crossing effects.

The AltiKa radiometer operates in dual-frequency channel microwave radiometer:

  • 23.8 GHz+/- 200 MHz: Brightness temperature measurements give information related to the water vapor content.
  • 37 GHz +/- 500 MHz: Brightness temperature measurements give information about cloud liquid water.

Both Brightness temperatures, in addition to the altimeter estimated backscatter coefficient σ0, are applied to calculate the troposphere correction range.

The radiometer must be swiffed- off during radar altimeter emission.


Radiometer band 23.8 GHz +/- 200 MHz - 37 GHz +/- 500 MHz
Radiometric sensitivity < 0.3 K
Radiometric Bias < 1 K
Radiometric averaging 200 ms
Rss feedsContactPartnersFAQLexiconLegal noticePersonal Data Protection PolicyMobile
You must enable cookies in your browser preferences to save the modifications
You are using an older version of Internet Explorer, please update to take full advantage of Aviso+ features

Customize the home page

View all widgets
Reduce display
Public profile
User profile

Select/Deselect widgets

Discover AVISO+

Customizable home, reading tools, products search guide, etc.. Discover step by step the features of the new site AVISO+.

Customizable homepage

This home page is composed of blocks called "widgets".

Rearrange the blocks with a "Click & Drop".

Hide a widget with the cross at the top right. Reset or add a widget with the "wrench" icon. The "User" and "Public" profiles offer a predefined organization.

All the modifications are automatically saved as cookies on your machine so as to enable you to have your own specific AVISO+.

Reading tools

Ease your reading by choosing the page background colour (black/white) and/or by modifying the font size.

Browsing menu and breadcrum trail

To ease your browsing through AVISO+, you can use at any time the main banner items with the interactive submenus or use the browsing menu on the left side of the screen (it is open by default). For more readiness of the page contents, you can fold and unfold the browsing menu by clicking on the tab. At any time you can know where you are thanks to the browsing menu or the breadcrum at the top of the page.

Products search guide

The first submenu of the "Data" banner item leads you to a new search form enabling you to find quickier the product that suits your needs. The list of results is updated according to your selection criteria.

AVISO+ Multimedia

The first submenu of the "Multimedia" banner item leads you to AVISO+ collections of images and videos linked to altimetry and its applications. Have a nice visit!