One of the most promising remote sensor for 3D mapping of wind vector is the Doppler Radar instrument. We present here the results of the DORA activity where the antenna and the main components which are necessary to make it work have been designed. The critical component has been identified in a special type of rotary joint able to pass two dual polarized RF channels from the fixed to the...
In this activity, we develop novel focal plane detector pixels for the next generation CMB B mode detection missions. Such future mission designs will require focal plane pixel technologies that optimizes the coupling from telescope optics to the large number of detectors required to reach the sensitivities required to measure the faint CMB polarization traces. As part of an ESA Technical...
In this research contract, we developed a number of different electromagnetic simulation tools targeting the development of focal plane detectors for future submillimetre astronomy and Cosmic Microwave Background (CMB) polarisation missions. We developed new technology solutions for the horn antenna feeds and detector coupling structures that can meet the technical requirements of the next...
Additive manufacturing (AM) methods are nowadays considered as a promising alternative for the fabrication of complex RF components for space applications. Among all the AM technologies, selective laser sintering (SLS) is currently the most explored technique for space applications. This is mainly motivated by the characteristics of materials used (such as metals and ceramics), for which most...
Microwave radiometers have a long heritage of providing a dedicated wet tropospheric correction to the path delay of radar altimeter pulses and echo backscatter due to water vapour content within the troposphere. With the introduction of synthetic aperture processing in radar altimetry, more accurate altimetry data is anticipated for coastal and inland waters. Therefore, the objective of this...
The wet tropospheric correction (WTC) is a major source of uncertainty in a radar altimetry budget error, due to its large spatial and temporal variability: this is why the most altimetry missions include a microwave radiometer. With the introduction of the along-track synthetic aperture processing, first implemented in CryoSat-2, and now in the upcoming operational altimetry missions such as...
Spaceborne imaging microwave radiometers for Earth observations can determine a multitude of properties of land and oceans, by measuring the brightness temperature emitted by the Earth. For ocean observations, ocean surface wind vector, sea surface temperature and sea ice characteristics are important parameters, normally measured in C band, at 6.9 GHz.
The above instruments are defined by...
The main objective of this project (performed by Airbus Defence and Space Spain) is to perform an exhaustive trade-off for multi-functional antennas, mainly focused on the combination of NAVANT L-band and Search and Rescue antennas (RX UHF antenna and TX L-band antennas), which are the biggest antennas in the GALILEO satellites antenna farm. The trade-off covers a broad range of possibilities...
The Wavemill is an RF instrument which follows a pure along-track interferometer concept, the
'Javelin’ one. In the Javelin architecture, master and slave phase centres should be perfectly
aligned in the along track direction, and the resulting interferogram, co-located, is only sensitive to
surface motion. The objective of the Wavemill instrument is to combine along and across track radar...
SMOS has been in orbit for more than 8 years, which has allowed to learn significantly on the reconstruction process of the synthetic aperture radiometer and the influence of the correspondent calibration parameters. One of the remaining artefacts to be corrected is the spatial ripple that can be observed in the brightness temperature images even if in perfect calibration conditions and...
The objective of this activity is to realise an active breadboard for integration with an existing feed horn-array, populated with COTS LNA MMIC’s, waveguide interfaces, and SMP- and DC-connectors consisting of 7 RF-channels in total. The frequency band is 35.5-36 GHz. Each channel has one LNA that can be switched on or off via an external control line, and a coupler for calibration purposes....
The proposed activity aims at bringing to TRL 5 an X-band medium-to-high gain antenna system based on the modulated MTS concept. This concept has been the subject of a number of projects financed by the European Space Agency and the Italian Space Agency, which have demonstrated up to TRL 4 the unique flexibility of MTS antennas in the choice of radiation pattern and polarization using the same...
The study has been devoted to the design of X-band TTC antenna on enlarged bandwidth (7.19-7.25 GHz and 8.025-8.400 GHz) and K-band DDL antenna (25.5-27.0 GHz) for Future Low Earth Orbit missions. An innovative TTC antenna has been defined with a compact envelope and good RF performance. The TTC antenna design is based on aperture surface impedence control over wide frequency bandwidth to...
This paper describes a Ka band antenna S/S for downloading data from Low Earth Orbit satellites (LEO’s) with costant power flux density (PFD) on earth, as requested in typical Low Earth Orbit satellites (LEO’s) orbiting at 500 Km attitude. The antenna consists of a small electronically steerable planar phased array magnified by a rotationally symmetric double reflector system. The passive...
In parallel to KABESA project (Ka Band Payload Data Downlink Electronically steerable Antenna), Thales Alenia Space in France was awarded by ESA for the development of a Ka band ferrite phase shifter (ESA Contract No 4000111738).
Indeed, this ferrite phase shifter is the key device which provides the electrical beam scanning functionality while allowing a high efficient solution thanks to the...
Within the frame of this activity we have investigated the multipactor effect when dielectric and ferrite materials are present in a component.
To do so, specific designs have been implemented in order to evaluate the breakdown power level. In addition to that, simulations have been performed in order to determine the ability of numerical techniques to predict the multipactor breakdown levels...
Within the frame of this activity we have investigated the impact of different modulation schemes in the multipactor breakdown power levels in different passive components.
Simulations ans tests have been compared in order to demonstrate the ability of current tools to analyse multipactor under such conditions. In particular, SPARK3D and CST Particle Studio have been used for such a purpose.
The design and development of low cost planar S-band diplexers for CubeSats is presented. Technology and topology considerations are discussed in detail. Electrical and mechanical design is presented. Results of BB measurements are presented and discussed. Manufacturing aspects are discussed with reference to final performance. Eventually, CubeSat compatible low cost planar S band diplexer...
In this Thesis, several novel design techniques for waveguide low-pass filters (LPFs) and band-pass filters (BPFs) are proposed. Firstly, a quasi-analytical technique for classical corrugated waveguide LPFs is presented. It allows to reduce the design-times and its associated costs, since the final dimensions of the final prototype are computed by closed-form expressions. This technique has...
The goal of this project is to demonstrate a miniature Timing Source (mTS) with low power consumption and frequency drift at least one order of magnitude better than more bulky Oven Controlled X-tal Oscillators (OCXO). The latters are currently considered the best available option in Space for timekeeping applications. The mTS technology is based on Orolia’s commercial rubidium clock adapted...
This report focuses on the critical design of the key T/R functions of high power amplification, low noise amplification and switching for the design of a C-Band GaN single chip front end (SCFE) for radar applications. The designs are performed on a commercial European 0.25um GaN process technology. Circuit architectures for the HPA, LNA and T/R switch are considered in order to meet a target...
Introduction
Schottky components are required for future space instruments and for emerging terrestrial applications in millimetre-wave imaging employed in the generation of the local oscillator signal and/or downconversion of the signal. This activity aimed at the development of a novel Transverse diode.
Objectives
The main objectives of the activity were:
(1) To develop discrete...
The increasing complexity and stringent performances required in RF instruments and payloads demand more and more that functional verification be performed on the integrated satellite under the most realistic operational conditions.
Due to accuracy and testing speed, Near field methods are very attractive techniques for such testing. However, in standard Near field testing of small antennas on...
This talk aims to shortly present the ESA Patent Porfolio and explain the way to request a license for the use of the patents listed in the Portfolio.
Several recent patents in the domain of microwave parts will be briefly also presented.
The objective of GRL project is to build a Level 1 processing module as a series of standalone processing building blocks for radiometric and geometric image processing for Earth Observation space-born sensors.
Starting from raw data (Level 0), orbit/attitude and sensor auxiliary info, GRL Level 1 Processing Module is able to generate Level-1 products applying radiometric and geometric...
Optical space sensors and their optionally supporting calibration devices are generally characterised pre-flight and calibrated against an on-ground traceable radiometric reference. However, both instruments and calibration devices are then exposed to space environment and susceptible to radiometric degradations once in operation. This results in a loss of traceability as soon as optical...
The objectives of the HYPOS project (ESA ITT AO/1-8345/15/NL/LvH ) are to assess the accuracy of the biophysical parameters using full hyperspectral information or reduced hyperspectral information assess the potential of the red edge spectral bands to estimate mainly the two vegetation biophysical variables, leaf area index (LAI) and leaf or canopy chlorophyll content. To achieve this goal,...
