19, January 2022

ESA Open Invitation to Tender: 1-10943
Open Date: 18/01/2022 15:26 CEST
Closing Date: 02/03/2022 13:00 CEST

Bi-static radars for future Earth Observation Missions would need a dedicated ground transponder due to the distance between the transmitter and receiver. The usual corner-reflector type transponder is not appropriate and a new concept needs to be developed.Retro-directive antenna transponders are able to substitute the passive corner reflectors and could be a good candidate for bi-static radars. Retro-directive antennas with an analog/digital hybrid delay-locked-loop (DLL) phase conjugator have a number of features that make them suited for such applications. One of these features is that the retransmitted signal can have a different direction as the incoming signal and this delta angle can be tuned for the specific distance between satellites. DLL based phase conjugation has already been demonstrated at K/Ka-band frequencies and should be easier to implement at typical C/L-band SAR radar frequencies. The activity should comprise development and design, critical breadboarding and test of such active retro-directive transponder for bi-static use. Besides the active transponder solution also an investigation shall be done regarding possible passive calibration targets. The frequency of the breadboard shall be either C-band or L-band.The activity encompasses the following tasks:- Selection of a mission scenario for the bi-static SAR- Identification of transponder requirements- Design and analysis of active/passive calibration target (transponder)- Manufacture and test of active/passive calibration target (transponder)- Conclusions and development plan.Procurement Policy: C(1) = Activity restricted to non-prime contractors (incl. SMEs). For additional information please go to this link.

Directorate: Directorate of Tech, Eng. Quality
Estabilishment: ESTEC
ECOS Required: No
Classified: No
Price Range: 200-500 KEURO
Authorised Contact Person: Anze Singer
Initiating Service: TEC-EFA
IP Measure: C1
Prog. Reference: E/0901-01 – Technology Developme
Tender Type: Open Competition
Technology Keywords: 7-A-III-Array Antennas and Standalone Radiators
Products Keywords: 4-B-1-a-Structure & Thermal, Servo / Mechanics, Reflectors, feeds and diplexers, Antenna Control Units (ACUs), Drive Systems / 4-B-4-a-Quartz clocks

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