Opportunities

Pre-doctoral and post-doctoral grants

The CommSenseLab has different openings for pre-doctoral and post-doctoral positions. These openings are linked to external calls with deadlines around mid October. In case you are interested in applying, please contact as soon as possible the listed project responsible.

Integrated photoconductive antennas at terahertz for sensing and communications
Electromagnetic modeling of biological cells
Modeling electromagnetic field enhancement at clusters of nano-particles
Detection and monitoring of vascular implants based on Microwave and RF Technologies
Towards the automatic detection of atmospheric pollen types and concentration
Reconfigurable RF monolithic integrated transmitter for sensing and communications
Femto-Farad Capacitive Sensors utilizing High Power RF MEMS Switches
Remote Sensing data processing and fusion: Atmospheric Boundary-Layer monitoring in the context of severe storm hazards
Development of new point-of-care biosensors based on RF MEMS
Microwave interaction with living organisms
Advanced mm-wave and terahertz communication and sensing systems
Wireless sensor antennas for the Internet of Things
Biomedical applications of radar remote sensing
Compact polarimetric radar sensors for UAV
Geostationary Synthetic Aperture Radar missions (GEOSAR)
Adaptive multi-spectral optical sensors for nano-satellites
Advanced Attitude Determination and Control Systems (ADCS) for nano-satellites
Advanced Earth Observation Techniques using Signs of Opportunity
Geophysical parameters retrieval from remote sensing measurements using synergies with data from different satellites
Contribution of multi-wavelength depolarization configurations to aerosol typing with lidar products
Effect of hygroscopic growth on aerosol optical properties in coastal regions
Assessment of atmospheric pollen classification with polarization-sensitive aerosol lidars
Development of a dual-polarization cloud radar at 35 GHz for the study of aerosol-cloud interactions

Integrated photoconductive antennas at terahertz for sensing and communications

Description

The terahertz band of the electromagnetic spectrum offers the possibility of high-capacity wireless communications and the implementation of new environment sensing systems. The development of such systems is hindered by the lack of efficient sources at the terahertz band. Photoconductive antennas are good alternative to terahertz generation at the low terahertz band. The availability of photonic components at 1500 micrometers developed for the optical communication needs opens the field for the development inexpensive of photoconductive terahertz sources for communication and sensing.

The candidate should address both theoretical aspects of modeling the photoconductive generation process as a means of increasing its efficiency. Aspects to be considered are new materials, plasmonic excitation of electrodes, new electrodes geometries, antenna matching. It is also expected to address the manufacturing and testing processes of the designs.

Candidate requirements: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications or electronic engineering or in physics. They should have a background in applied electromagnetism and solid state physics.

Responsible/Contact person: Jordi Romeu (romeu@tsc.upc.edu)

Electromagnetic modeling of biological cells

Description

Modeling the interaction of electromagnetic waves with biological cells is challenging due to the small width of the cell membrane layers compared to the wavelength. Existing approaches based on integral equations discretized by method of moments must be adapted for stability at very low frequencies. A new discretization scheme for surface and/or volume integral equations must be developed to avoid ill-conditioned method of moments linear systems.

Candidate requirements: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications, electronic engineering, physics or applied mathematics. They should have a background in electromagnetism, electromagnetic waves, vector and differential calculus, and programming.

Responsible/Contact person: Juan M. Rius (rius@tsc.upc.edu)

Modeling electromagnetic field enhancement at clusters of nano-particles

Description

Localized surface plasmon resonances (LSPRs) at noble-metal nanoparticles, enhance and confine electromagnetic fields in the near-infrared and visible parts of the spectrum. Applications in nanophotonics or biosensing need the development of electromagnetic simulators, which are challenging since the nanoparticles geometry must be discretized with very fine meshes leading to huge linear systems and the electric field integral equation becomes ill-conditioned. This thesis will address the problem by adapting existing fast solvers and using high-performance computing.

Responsible/Contact person: Juan M. Rius (rius@tsc.upc.edu)

Detection and monitoring of vascular implants based on Microwave and RF Technologies

Description

Stents are medical devices that are implanted inside blood vessels to restore partial occlusions (stenosis). Patients with stents require chronic medication and periodic monitoring to prevent several types of stent-related problems, particularly restenosis, which may be due to the growth of neointimal cells in and around the stent, or to the formation of artherosclerotic plaque. Such monitoring may include techniques which are either invasive or expose patients to ionizing radiation. Novel techniques based on RF and microwaves may facilitate patient monitoring by reducing cost and collateral effects. This thesis will study and develop of sensors, signals and systems for detecting and monitoring vascular implants (stents) using microwave technologies.

Responsible/Contact person: Juan M. O’Callaghan (joano@tsc.upc.edu)

Towards the automatic detection of atmospheric pollen types and concentration

Description

Atmospheric pollen and fungal spores are known to cause respiratory problems in ~ 30 % of the population in Western Europe. Automatic atmospheric pollen and spore concentration measurements are essential to provide real-time information to the population and also to constrain pollen and spore forecast models. At present the Hirst method, the method accepted internationally to collect pollen grains from the air, provide samples that, analyzed by a palynologist under a light microscope permits to distinguish between types and to calculate their concentration, is very time- and manpower-consuming which makes pollen and spore detection not real-time and of low time resolution (usually 24 hours).

This project proposes to evaluate and improve new sensors, already existing or in development. The methods used are usually light scattering or holography. Although not all of these sensors were developed specifically for the detection of pollen and spores, they all can be applied to it. In order to evaluate the performance of each sensor, direct comparisons between the new sensors and the Hirst method, used as the truth, will be made. The performances of interest are species recognition, pollen grain counting and the retrieval of extra properties (shape, size, color), if any, that may be useful at a later stage. Industrial and/or academic partners are required in this project in order to work directly at the hardware level towards the potential improvement of the sensors. In a simplified manner, the most suitable sensor will be the one which can recognize the higher number of pollen and spore types and retrieve their concentration with the lowest uncertainty.

Responsible/Contact person: Michaël Sicard (msicard@tsc.upc.edu)

Reconfigurable RF monolithic integrated transmitter for sensing and communications

Description

Actually many sensors situated close or inside the human body monitor and transmit information via radio. The biologic tissues influence the behaviour of the sensor antenna, like in a mobile phone, producing mismatching in the RF power amplifier output. That means more power consumption, more heat and less battery life.

The objective of this work is integrating in CMOS technology a reconfigurable/adaptive tuning filter together with a high efficiency power transmitter and other subsystems in order to match the power amplifier to an antenna under variable conditions.

Due to the frequency bands allowed, filters with lumped elements have to be used into integrated circuits because of the size of stubs and transmission lines at such frequencies. To avoid the use of inductors, techniques borrowed from low frequency electronics will have to be extended to RF, like active filters. Capacitors used in those filters can be made with MEMS (Micro Electro-Mechanical Systems)

Candidate requirements: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications or electronic engineering. They should have a background in microwave technology, particularly in software simulation tools (ADS, Cadence, CST,...).

Responsible/Contact person: Antoni Barlabé (barlabe@tsc.upc.edu)

Femto-Farad Capacitive Sensors utilizing High Power RF MEMS Switches

Description

RF MEMS switches have the potential to replace conventional PiN diode and MOS switches due to their better RF performance and linearity. They also have proven to handle high power without compromising their RF performance.

The objective of this work to come up with a novel topology of RF MEMS switches that can address reliability issues including charge trapping, sticktion, and the same time exhibits high speed actuation. Electrostatic actuation mechanism will be investigated to achieve a Femto Farad actuator that can sense any variation in the surrounding environment in terms of the permittivity. Other actuation mechanism will also be investigated to integrate the capacitive sensor. The developed high power RF MEMS switch will be able to route the desired signal to the appropriate destination.

Candidate requirements: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications or electronic engineering. They should have a background in microwave technology, particularly in software simulation tools (ADS, HFSS, CST,...). Background in Fabrication is a plus.

Responsible/Contact person: Lluis Pradell (pradell@tsc.upc.edu), Maher Bakri-Kassem (mbakrikassem@aus.edu)

Remote Sensing data processing and fusion: Atmospheric Boundary-Layer monitoring in the context of severe storm hazards

Description

Synergetic remote sensing of the atmosphere, combined with adaptive/data-fusion techniques, offers unprecedented capabilities to characterise the evolution of the Atmospheric Boundary Layer (ABL) and its critical role in the development of severe storms and associated hazards. Using long-duration, high-resolution, vertically pointing observations from active and passive ground-based remote sensing systems including, e.g., ceilometers, Doppler lidar, FMCW radar, and new technologies of microwave radiometers, it is expected to characterise ABL development over distinct regions that are well known for their relatively high tornado frequency.

The candidate will address data-fusion techniques based on adaptive estimation and/or machine learning that are to provide automated or semi-supervised identification of ABL top in non-precipitation observations, as well as classification metrics. Verification of ABL heights against independent observations from a wealth of remote-sensing instruments across collaborating U.S. research institutions (including e.g., Purdue University, NOAA and Univ. of Massachusetts) will also be a goal. The proposed work is expected to fill knowledge gaps related to characterisation and forecasting of such weather phenomena.

Candidate requirements: (i) Post-doc profile: Recent Ph.D. in telecommunications, electronic engineering, or physics with application to atmospheric remote sensing and data processing. Good English speaking and writing skills.

(ii) Ph.D. profile: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications, electronic engineering, or physics with clear motivation to study atmospheric remote sensing and data processing. Good English command.

Responsible/Contact person: Francesc Rocadenbosch (roca@tsc.upc.edu )

Development of new point-of-care biosensors based on RF MEMS

Description

Traditionally biological samples are analyzed using microfluidic circuits by measuring the changes that the sample produces in the impedance. This technique, however, is only able to detect markers that are present in a high concentration. As an alternative, the use of RF and microwave frequencies allows the fast and accurate measurement of biological markers present in a low concentration, for example for detection of cancer tumor cells. In this work, RF and microwave techniques will be applied to microfluidic circuits, integrating new micro-electro-mechanical devices (MEMS) with the purpose of developing point-of-care biosensors. In the microfluidic section, the device includes all the elements for the biological sample pre-treatment (filtration and mixing). The RF section includes all the necessary circuitry for the signal detection and post-processing. Mechanical design software will be used for the definition of the microfluidic elements, while the design of the MEMS devices and the microwave circuits will be performed using software for electromagnetic and circuit simulation.

Candidate requirements: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications, electronic engineering, physics or mechanical engineering. They should have a background in microwave technology, microfluidics and software for electromagnetic simulation (ADS, Cadence, HFSS) and mechanical simulation (ANSYS, Fluent) is desirable.

Responsible/Contact person: Lluís Pradell (pradell@tsc.upc.edu) and Jasmina Casals (jasmina.casals@upc.edu)

Microwave interaction with living organisms

Description

The possibility of a wireless interaction with the living organisms is a field that would open a big range of new possibilities and applications. Electromagnetic waves and microwaves in particular may offer the possibility to sense the biological activity of these organisms due to its capability to propagate into biological media and to interact with the electrical activity relied to the physiological functional activity. These interactions may cover from the microorganisms to the brain functional activities. The study will cover from the electromagnetic modelling of the biological bioelectromagnetic system to the design of microwave transceivers able to transmit and receive signals to and from the biological medium.

Candidate requirements: Candidates should meet the academic requirements to enter the PhD program. They should hold a degree in telecommunications or electronic engineering or in physics. They should have a background in applied electromagnetism and microwave radiation and electronics.

Responsible/Contact person: Lluís Jofre (jofre@tsc.upc.edu)

Advanced mm-wave and terahertz communication and sensing systems

Description

The unstoppable evolution towards a highly connected environment will require a new generation of communication and sensing devices with very demanding requirements in terms of miniaturization, energy consumption and sensing sensitivities for different kinds of chemical, biological and electrical devices. To respond to these requirements new approaches to the wireless system architectures will be studied and new forms of radiation systems will be designed and tested. The work will cover from the electromagnetic characterization of the operating environment (both inert and living matter), the radio system transceiver optimization up to the sensing mechanism and its connection to the radio system.

Responsible/Contact person: Lluís Jofre (jofre@tsc.upc.edu)

Wireless sensor antennas for the Internet of Things

Description

The work will address the analysis, modeling and design of the next generation of wireless front-end communication, sensing and imaging system architectures able to respond to the new demands for improving up to 3 orders of magnitude in terms of capacity, efficiency and connectivity. A system-based approach will study the central aspects as antennas and RF front-ends, radio signal propagation, and integration challenges. The study will explore emerging fields such as the "connected car" or the "100 Gbps connectivity" scenarios. Concepts like reconfigurability, terahertz photonics, and Massive MIMO will be addressed. The work will include the modeling, simulation and experimental validation.

Responsible/Contact person: Lluís Jofre (jofre@tsc.upc.edu)

Biomedical applications of radar remote sensing

Description

Recent experimental studies have evidenced the potential use of millimetre wave and THz radar techniques for patient remote observation and vital parameters measurement. The evolution of radar technology and the trend towards Radar Systems on a Chip (RSoC) enables the proposal of low-cost compact radar sensors tailored to diverse health monitoring and diagnostic. The proposed work is centred in the proposal and research of new low power, high resolution radar sensors and associated data processing, according to the clinical needs and technical requirements resulting from the ongoing cooperation with leading research hospitals in Barcelona.

Candidate requirements: (i) Post-doc profile: Recent Ph.D. in telecommunications or electronic engineering, or physics focused on sensing or imaging techniques and systems based on microwaves and THz with potential applications to life sciences, health care and medicine. Knowledge and/or experience in biomedical techniques/applications is desirable. Good English speaking and writing skills required.

(ii) Ph.D. profile: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications, electronic engineering, or physics with a clear motivation to carry out research on innovative sensing and imaging concepts based on microwaves and THz. Good English command required.

Responsible: Jordi Mallorquí (mallorqui@tsc.upc.edu)

Compact polarimetric radar sensors for UAV

Description

Airborne Synthetic Aperture Radar (SAR) sensors have been commonly used during the last decades to monitor different phenomena in medium-scale areas of observation, such as object detection and characterization or topographic mapping. The use of Unmanned Aerial Vehicles (UAVs) is a cost-effective solution that offers higher operational flexibility than airborne systems to monitor these type of scenarios. The Universitat Politècnica de Catalunya (UPC) is developing the first fully polarimetric SAR system at X-band integrated into a small UAV Multicopter Platform (UAV MP). The sensor, called AiRBased REmote Sensing (ARBRES), has been integrated into the platform overcoming restrictions of weight, space, robustness and power consumption. Nowadays, polarimetry in SAR systems plays an important role in radar remote sensing and it has many applications in many fields as natural hazard monitoring, agriculture, oceanography, etc. The proposed research will be involved in the development and validation of a polarimetric radar system ARBRES POLSAR, based on a small unmanned aerial vehicle platform (UAV), and prepared to carry out PolSAR and PolInSAR measurements.

Candidate requirement: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications or electrical engineering and interest or background in electronic or microwave systems design and simulation.

Responsible: Xavier Fàbregas (fabregas@tsc.upc.edu) / Albert Aguasca (aguasca@tsc.upc.edu)

Geostationary Synthetic Aperture Radar missions (GEOSAR)

Description

Radar Earth Observation missions are based on Low Earth Orbit (LEO) Synthetic Aperture Radar (SAR) Satellites providing accurate metric resolution images of stable scenes. However Fast or medium dynamics phenomena such natural disasters (Landslides, Earthquakes, Volcanology, etc.) and particularly meteorological parameters vital for numerical weather prediction models cannot be properly monitored with LEOSAR satellites due to the long revisit time (> 10 days typically) associated with low orbits.

Operating a radar from a Geostationary platform (GEOSAR) would be ideal to provide continuous imaging and monitoring, expanding the geographical coverage from present regional scale to a continental scale. Present research in GEOSAR is addressed, in the context of a European consortium, to find appropriate solutions and optimization in the aspects of satellite orbit precise determination, multiplatform operation (MIMO), atmospheric change compensation and antenna beam steering techniques. The proposed techniques will be simulated and experimentally validated using existing satellites.

Candidate requirement: Candidates should meet the academic requirements to enter the Ph.D program. They should hold a degree in telecommunications or electronic engineering and interest or background in electronic or microwave systems design, simulation and characterization.

Responsible: Antoni Broquetas (broquetas@tsc.upc.edu)

Adaptive multi-spectral optical sensors for nano-satellites

Description

FFSCAT mission is the winner of the 2017 “Copernicus Masters” “ESA Sentinel Small Satellite (S^3) Challenge.” FFSAT is an innovative and groundbreaking mission consisting of two federated 6U Cubesats (3Cat-5/A and 3Cat-5/B) in support of the Copernicus Land and Marine Environment services (Sentinels 1, 2, 3), to measure soil moisture, ice extent and thickness, and to detect melting ponds over ice, and to test techniques for future satellite federations.

With an innovative dual microwave payload (microwave radiometer + GNSS-Reflectometer) in 3Cat-5/A, a multi-spectral optical payload in 3Cat-5/B, and radio & optical inter-satellite links, and an Iridium inter-satellite link, FFSCAT aims at advancing in the fields of advanced payloads for small satellites and in the field of “federated satellite systems.” FFSCAT will be the precursor of a scalable constellation of federated small Earth Observation satellites having the potential to dramatically change the way ESA procures its satellites in the future.

This Ph D position is focused on the design, development and test of the space-borne multi-spectral optical payload in 3Cat-5/B. This payload is a medium resolution (< 10 m), wide field-of-view imager, with 4-5 spectral bands based entirely on COTS (commercial off-the-shelf) components. These components include high resolution imaging sensors, tunable optical filters, and zoom lenses, that must be qualified to withstand the thermal cycling, vacuum, and vibration tests to make them ready for space-borne applications.

Candidate requirement: Candidates should have a background in electronics, optics, signal processing (image compression), with a special interest in Earth Observation.

Candidates must also be capable of working collaborative in teams, aiming to the highest level of quality in their work, and be able to support the stress generated when having to meet with deadlines, deliverables to ESA etc. as in any real space project.

Responsible: Adriano Camps (camps@tsc.upc.edu)

Advanced Attitude Determination and Control Systems (ADCS) for nano-satellites

Description

FFSCAT mission is the winner of the 2017 “Copernicus Masters” “ESA Sentinel Small Satellite (S^3) Challenge.” FFSAT is an innovative and groundbreaking mission consisting of two federated 6U Cubesats (3Cat-5/A and 3Cat-5/B) in support to the Copernicus Land and Marine Environment services, to measure soil moisture, ice extent and thickness, and to detect melting ponds over ice, and to test techniques for future satellite federations.

With an innovative dual microwave payload (microwave radiometer + GNSS-Reflectometer) in 3Cat-5/A, a multi-spectral optical payload in 3Cat-5/B, and radio & optical inter-satellite links, and an Iridium inter-satellite link, FFSCAT will be the precursor of a scalable constellation of federated small EO satellites having the potential to dramatically change the way ESA procures its satellites in the future.

Both nanosatellites will be equipped with state-of-the art magnetorquers and reaction wheels as “actuators,” and magnetometers, gyroscopes, Sun sensors, and star trackers as “sensors.” This Ph. D. position is focused on the design, simulation, development, and test of advanced Attitude Determination and Control Systems (ADCS) for small satellites to meet the stringent requirements of medium/high resolution optical payloads (high stability, low jitter, and maneuverability or pointing agility).

Candidate requirement: Candidates should have a strong background in aerospace/aeronautics engineering and control theory, and knowledge in electronics, optics, and programming to understand in detail how the different sensors and actuators operate, and which are their limitations. The candidates should also be able design and give the technical specifications of the next generation of ADCS systems to meet the requirements of the next generation of Earth Observation platforms.

Responsible: Adriano Camps (camps@tsc.upc.edu)

Advanced Earth Observation Techniques using Signs of Opportunity

Description

Although originally designed for navigation, signals from the Global Navigation Satellite System (GNSS), i.e., GPS, GLONASS, Galileo and Beidou, exhibit strong reflections from the Earth and ocean surface. Dielectric and surface roughness properties modify the properties of the reflected signals, allowing to invert these effects to retrieve geophysical data such as ocean surface winds, soil moisture, vegetation water content…

GNSS-Reflectometry (GNSS-R) techniques enable the use of small, low power, passive instruments, that can be deployed on small satellites, balloons and UAV’s.

Extensive sets of airborne GNSS-R measurements have been collected over the past 20 years. First space-borne GNSS-R data were collected by the UK-DMC satellite (2003), followed by UK TDS-1 (2014), and NASA CYGNSS, an 8-satellite constellation launched in December 2016. Despite these advances, there are still lots of unresolved issues that require to be investigated to fully exploit these techniques:

Development of soil moisture and vegetation water content retrievals,
Surface topography correction,
Ice cover mapping,
Development of imaging algorithms as a bistatic unfocused synthetic aperture radar, and
Multi-look processing for improved target detection.

Candidate requirement: Candidates should have a strong background in remote sensing, electromagnetism and scattering, signal processing, GNSS systems, to understand in detail the signals properties, the sensors architecture, to develop data processing and retrieval algorithms.

Candidates should be interested in conceiving, designing and operating sensors to gather experimental data (i.e. airborne, stratospheric balloon…), and to use existing data from satellite missions, namely NASA CYGNSS, and the upcoming 3Cat-4 and FSSCAT - 3Cat-5/A from UPC, to address the above issues. Collaborative team working is required, aiming to the highest level of quality in their work, and being able to support the stress generated when having to meet with deadlines, deliverables to ESA etc.

Responsible: Adriano Camps (camps@tsc.upc.edu)

Geophysical parameters retrieval from remote sensing measurements using synergies with data from different satellites

Description

Theoretical and experimental evidence have suggested that L-band radiometry is optimal for soil moisture sensing. The European Space Agency’s (ESA) Soil Moisture and Ocean Salinity (SMOS) mission, launched in November 2009, has on board the L-band radiometer MIRAS (Microwave Interferometric Radiometry by Aperture Synthesis). On the technological side, the MIRAS has proved to be very stable and robust, providing high-quality measurements. On the scientific side, the SMOS data have exceeded all expectations. In particular, maps of the main mission variables (soil moisture and sea surface salinity) are currently served with higher accuracy and resolution than foreseen. Moreover, new emerging applications of high societal impact are currently being derived and exploited from SMOS data, as well as the L-Band NASA’s mission SMAP (Soil Moisture Active and Passive).

The proposed research activity is intended to study, design and validate innovative algorithms for obtaining added value products. One of the main objective will be to develop an algorithm for simultaneously obtaining the Soil Moisture, the Vegetation Optical Depth (VOD) and the albedo, taking advantage of the multi-angular measurements from MIRAS. It will be important to enhance the accuracy in critical areas such as, coastline or areas with high radio frequency interferences (RFI).

On the other hand, the new high resolution soil moisture product developed at Barcelona Expert Center (BEC), will be used with other data, such as land surface temperature, and vegetation information (VOD or NDVI) for developing algorithms for predicting biomass, crop yield, drought effects, forest fire risk and other new applications, useful for climate change and agricultural and forestry applications.

The work will be carried out as part of a research team involving other researchers and staff from other universities and research centres such as CSIC. Envisaged phases of the work are training on remote sensing technology (radiometer and radar) and processing, study of state of the art, capture and critical review of data requirements. The new products will be validated with ground truth data and databases. Proposed work includes the proposal and preparation of publications submitted to reference journals and participation in international conferences, as well as the writing and defence of a PhD Thesis on the research results.

The international dimension of the proposed work will benefit from CommSensLab expertise in European projects in both passive remote sensing and earth observation and participation in future Calls of H2020

Candidate requirement: Candidates should meet the academic requirements to enter the PhD program. They should hold a degree in telecommunications, electronic engineering, or physics with a clear motivation to carry out research on innovative sensing and imaging concepts based on microwaves.

Responsible: Mercè Vall-llossera Ferran (merce@tsc.upc.edu)

Contribution of multi-wavelength depolarization configurations to aerosol typing with lidar products

Description

Aerosol classification, also called aerosol typing, provides significant help to understand aerosol sources, their effects, and feedback mechanisms to improve the accuracy of satellite retrievals and to better quantify the effect of aerosols on climate change modelling. Lidar (light detection and ranging) systems are not only capable of identifying multiple layers in the atmosphere but also of classifying aerosols according to their capabilities of performing multi-wavelength and depolarization-sensitive measurements. Typically, the particle extinction-to-backscatter ratio, also called lidar ratio, and the particle linear depolarization ratio at one wavelength are considered for an aerosol characterization, as well as the wavelength dependence of aerosol extinction or backscatter coefficients. This project aims at exploring the benefits of lidar depolarization measurements at several wavelengths to assess a more accurate aerosol typing.

The job position consists of 1) performing the full characterization (calibration stability, retrieval of the volume and particle depolarization ratios and associated errors) of the two depolarization channels at 355 and 532 nm of the Remote Sensing Laboratory (RSLab) aerosol lidar; 2) implementing single and dual depolarization capabilities in an existing automatic classification procedure, and further training and testing of the algorithm; 3) possibly implementing the algorithm in the Single-Calculus Chain (SCC), the common calculus chain developed within EARLINET, the European Aerosol Research Lidar Network, for the automatic evaluation of lidar data from raw signals up to advanced aerosol products. Task 1) may include some small hardware level developments.

Candidate requirement: The candidate should meet the academic requirements to enter the PhD program. He/she should hold a degree preferably in telecommunications or electronic engineering, in physics or in applied mathematics, and have a background in optics, as well as in atmospheric sciences. The person appointed will be involved in both European- and national-funded projects and will collaborate with scientists of reputed international institutions. He/she will benefit from lidar operation and data processing expert training. We encourage applications from highly motivated candidates.

Responsible: Alejandro Rodriguez (alejandro@tsc.upc.edu) / Nikolaos Papagiannopoulos (nikolaos.papagiannopoulos@imaa.cnr.it)

Effect of hygroscopic growth on aerosol optical properties in coastal regions

Description

Water vapour is one of the most important constituents in the Earth’s atmosphere. It plays a key role in the Earth’s radiative budget and the energy transport mechanisms in the atmosphere. It shows a high variability in space and time, especially in coastal regions. In addition to being an important atmospheric variable on its own, water-vapour content has an effect on aerosol properties. Indeed, under high relative humidity conditions particle size may increase due to hygroscopic growth (also called water uptake) altering their size distribution and their associated optical and microphysical properties. This project aims at assessing the aerosol type-dependency and the seasonal variability of the aerosol hygroscopic growth factor in a coastal region and investigating its effect on the aerosol radiative forcing.

In more detail, the job position consists in assessing the effects of hygroscopic growth on aerosol optical and microphysical properties for different aerosol types and their effect on the aerosol radiative forcing. A first phase of the project will consist in investigating the possibility to study the aerosol hygroscopic growth from lidar data only, possibly substituting measurements of temperature profiles by profiles of standard atmospheric models, and estimating the uncertainties associated to this methodology. Then an analysis of the Remote Sensing Laboratory (RSLab) lidar database should be performed to assess the aerosol hygroscopic growth factor in Barcelona, Spain, paying special attention to transitions of sea-land breeze regimes, seasonal variations, possible correlations with the surface solar radiation, etc. A second phase of the project will consist in characterizing the enhancement of the aerosol scattering properties (and not only their extinction or backscatter properties) due to water uptake in order to later quantify the effect of water uptake on the aerosol radiative forcing.

Candidate requirement: The candidate should meet the academic requirements to enter the PhD program. He/she should hold a degree preferably in telecommunications or electronic engineering, or in physics, and have a background in optics, as well as in atmospheric sciences. The person appointed will be involved in both European- and national-funded projects and will collaborate with scientists of reputed international institutions. He/she will benefit from lidar operation and data processing expert training. We encourage applications from highly motivated candidates.

Responsible: Constantino Muñoz (constan@tsc.upc.edu) / Maria Jose Granados (maria.jose.granados@tsc.upc.edu)

Assessment of atmospheric pollen classification with polarization-sensitive aerosol lidars

Description

Atmospheric pollen and fungal spores are known to cause respiratory problems in ~ 30 % of the population in Western Europe. The way airborne pollen and spores are dispersed vertically in the atmosphere has been very little studied and always at the scale of an event and without distinction on the pollen type. The project aims at evaluating the capabilities of polarization-sensitive lidars to detect different pollen and spore types present along the years in sites of different biodiversity. The database that will be employed are the products of the polarized Micro Pulse Lidar (P-MPL) which is an automatic and continuous 24/7 aerosol lidar. Both of these systems are operating in the Iberian Peninsula in Barcelona and El Arenosillo (Huelva).

The project includes a close collaboration with 1) the Atmospheric Research and Instrumentation Branch of the Instituto Nacional de Técnica Aeroespacial (INTA), who operates a P-MPL in the atmospheric observatory of El Arenosillo (Huelva) since 2016 for the monitoring of Saharan dust intrusions and Cirrus clouds; and 2) the Laboratory of Palynological Analysis (LAP) of the Department of Animal Biology, Plant Biology and Ecology and the Institut de Ciència i Tecnologia Ambientals (ICTA) of the Universitat Autònoma de Barcelona (UAB) for their expertise in pollen measurement systems and the database on airborne pollen started in 1994.

The job position consists in conducting research to evaluate the capabilities that P-MPL systems have to detect atmospheric pollen and spores of different types, during different seasons and at sites of different biodiversity. The identification of pollen and spore types, pollination season and intensity will be made out of a multi-year database of surface concentration measurements from the Red Española de Aerobiología (REA). In the period considered, and after the removal of any long-range transport of non-pollen aerosol types, in order to avoid aerosol mixture in a first approach, we will look in the atmospheric column for the signature of the type of pollen/spore detected at the surface and present results in terms of pollen/spore responses and trends. Special attention will be paid to the predominant pollen/spore species at each site considered. In case of the presence of several pollen/spore types simultaneously, case studies will be deeply investigated in order to possibly discriminate between two or more species. These case studies may involve the multi-wavelength lidar system of the Remote Sensing Laboratory (RSLab) which has 2 depolarization channels, in order to have information not only on the value of the particle depolarization ratio but also on its spectral dependency. Indeed pollen grains are usually highly depolarizing particles and their signature is clearly visible on polarization-sensitive channels when no other depolarizing particles are present.

Candidate requirement: The candidate should meet the academic requirements to enter the PhD program. He/she should hold a degree preferably in physics or applied mathematics, and have a background in optics, as well as in atmospheric sciences. He/she will benefit from lidar operation and data processing expert training. We encourage applications from highly motivated candidates with human capabilities to work in a pluridisciplinary team.

Responsible: Michaël Sicard (msicard@tsc.upc.edu)

Development of a dual-polarization cloud radar at 35 GHz for the study of aerosol-cloud interactions

Description

The rapid changes in climate observed during past decades have important social and economic impacts on both global and regional scales that has brought climate change to the spotlight. According to the Fifth Assessment Report (AR5) of the last IPCC, atmospheric aerosol produces a net cooling effect of the Earth’s climate. The largest uncertainty associated to this estimation comes from the radiative forcing (RF) of aerosol-cloud interactions (ACI), formerly known as aerosol semi-direct and indirect (cloud-albedo and -lifetime) effects. Anthropogenic activity has led to an increase in aerosol particle concentrations globally and consequently to changes in cloud properties, as particles act as cloud condensation nuclei (CCN) and ice nucleating particles (INP). The observation and study of the ACI requires remote sensing instrumentation ideally formed by a set of aerosol lidar (Light Detection and Ranging), cloud radar and wind profiler. The overall objective of this proposal is to contribute to the current knowledge on vertical profiles of aerosol and cloud microphysical properties to understand aerosol-cloud interaction processes addressing in priority the semi-direct effect.

The job position consists in leading the project which is threefold: 1) technological development of a cloud radar, 2) simultaneous observations of aerosol, cloud and wind profiles, and 3) assessment of the ACI addressing in priority the semi-direct effect. Initially we propose to design a radar operating in the 35 GHz meteorological radar band for zenithal cloud observation based on the homodyne CW-Linear FM configuration using solid state power amplifiers and flexible sweep parameters to optimize the compromise between sensitivity and range-resolution. Because the distinction between liquid and solid cloud particles can only be achieved with measurement of the linear depolarization ratio, dual polarization measurements will also be considered. Once the cloud radar will be in operation, an intensive long-term observation period will be carried out in order to feed the database with coincident cloud radar and multi-wavelength aerosol lidar measurements. Radiative forcing calculations will be performed with the numerical tool ARTDECO (Atmospheric Radiative Transfer Database for Earth Climate Observation) in different scenes and cloud phases.

Candidate requirement: The candidate should meet the academic requirements to enter the PhD program. He/she should hold a degree in telecommunications or electronic engineering or in physics and have a background in applied electromagnetism and solid state physics. Experience in atmospheric sciences is also preferable. The person appointed will be involved in both European- and national-funded projects and will collaborate with scientists of reputed international institutions. He/she will benefit from long-lasting expertise in technological development of radar systems for multiple purposes, as well as lidar operation and data processing expert training. We encourage applications from highly motivated candidates with human capabilities to work in a pluridisciplinary team.

Responsible: Albert Aguasca (aguasca@tsc.upc.edu) / Michaël Sicard (msicard@tsc.upc.edu)

Contacto	usd.utgcnticupc.edu
Dirección	UPC Campus Nord, C/Jordi Girona 1-3, Edificios D3-D4-D5, 08034 Barcelona (SPAIN)
Teléfono	+34 934017486