L-BAND ANTENNA FOR NEXT GENERATION SMOS MISSIONS
20, May 2021

ESA Open Invitation to Tender: 1-10771
Open Date: 14/05/2021 12:47 CEST
Closing Date: 25/06/2021 13:00 CEST

ESA’s Soil Moisture and Ocean Salinity (SMOS) mission launched in 2009 is based on an L-bandinterferometric radiometer providing images of the entire earth globe every three days. Several studies havebeen conducted in the past few years to define a different antenna configuration which could allow to improve the image quality and simultaneously reduce the imaging time. An hexagonal array configuration withreduced inter-element distance emerged as the most promising solution with a halved spatial resolution and arevisit period reduced by a factor 3.This activity shall focus on the design of an hexagonal array antenna for the next generation SMOSradiometric instrument operating in L-band. The array needs a reduced element spacing, down to 0.57 lambda(at 1413.5 MHz), to allow an alias-free image.The activity shall include the manufacturing and test of a breadboard. Specifically, this breadboard, with areduced number of elements and including a ground plane large enough to avoid background radiation, shallbe defined and experimentally characterised. The polarisation axis of the array elements shall rotate with the arm, contrary to SMOS. The reflection coefficient over an adequate temperature range, the radiation patterns,the directivity and the gain shall be characterised for the isolated element and for several elements embeddedin the hexagonal array. The manufactured element shall fulfil the SMOS requirements in terms of loss, cross-polarization and port isolation. Moreover, a reduced mass compared to the current design is also required.The activity encompasses the following tasks:- Review of requirements- Critical design- Manufacture and characterisation of the breadboard

Directorate: Directorate of Tech, Eng. Quality
Estabilishment: ESTEC
ECOS Required: No
Classified: No
Price Range: > 500 KEURO
Contracts Officer: Anze Singer
Initiating Service: TEC-EFA
IP Measure: N/A
Prog. Reference: E/0901-01 – Technology Developme
Tender Type: Open Competition
Open To Tenderers From: AT+BE+CH+CZ+DE+DK+EE+EL+ES+FI+FR+GB+HU+IE+IT+LU+NL+NO+PL+PT+RO+SE
Technology Keywords: 7-A-III-Array Antennas and Standalone Radiators
Products Keywords: 2-I-1-c-Microwave radiometers

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