DEVELOPMENT OF LOW-BARRIER DIODES AND MIXERS FOR PASSIVE SUB-THZ RADIOMETER ARRAYS - EXPRO PLUS

Objective: To develop low barrier Schottky diodes and mixers for passive remote sensing of the Earth's atmosphere, with a local oscillator power requirement less than 25% compared to a traditional GaAs mixer.Description: Traditional Gallium Arsenide mixers such as the one used for MetOp-SG Micro Wave Imager (MWI) and Micro Wave Sounder (MWS) and Ice Cloud Imager (ICI) instruments need few milliwatts of local oscillator (LO) power to reach optimal conversion efficiency and noise figure. For single pixel instruments, this is well achievable with current local oscillator technology. For extended arrays of heterodyne receivers, this would mean to increase the local oscillator power requirements by one or two orders of magnitude. Therefore, the need for low LO power mixers is key to develop extended arrays of heterodyne receivers. This can be achieved by implementing a direct current (DC) biasing circuit together with GaAs mixer technology. This increases the complexity of the mixer circuit. An alternative solution is to implement low-barrier mixers using alternative semiconductor technology to reduce the barrier-height of the Schottky contact and similarly the pump power level, without the need for external DC biasing. The objective of this activity is to develop low-barrier diodes and mixers at EarthObservation applicable frequencies in the millimetre-wave and sub-THz regions of the spectrum. This activity encompasses the following tasks: - Review of the current state-of-the-art in terms of low-barrier Schottky technology available (InGaAs, SiGe,...). - Design, manufacture and test a low-barrier diode and mixer operating in the 166-664 GHz range - Perform analysis of the performance, lessons learned and propose roadmap for future developments.Procurement Policy: C(1) = Activity restricted to non-prime contractors (incl. SMEs). For additional information please go to:http://www.esa.int/About_Us/Business_with_ESA/Small_and_Medium_Sized_Enterprises/Opportunities_for_SMEs/Procurement_policy_on_fair_access_for_SMEs_-_the_C1-C4_Clauses.