PROJECT 3.2 Large focal plane for future astronomical instruments of the "The Radio Universe: astronomy and astrophysics at the JBCA 2014-2017"

Lead Research Organisation: CARDIFF UNIVERSITY
Department Name: School of Physics and Astronomy

Abstract

The project 3.2 "Large focal plane for future astronomical instruments" is divided in three parts:
3.2.1 Large scale high performance waveguide component manufacture.
3.2.2 Large diameter mesh-based quasi-optical components.
3.2.3 Accurate RF characterisation and systematic effect study.

The goals of the above studies are:

3.2.1 Development of waveguide components:
a) Using 3D printing (1 GHz to 200 GHz);
b) Based on metalised foam (1 to 30 GHz).
c) Based on Stacked rings (100 to 700 GHz).

3.2.2 Manufacture and tests of:
a) Large diameter embedded mesh-filter;
b) Large diameter lens.

3.2.3 RF characterisation of:
a) Assembled multi-pixel system;
b) Large lens.

As agreed, all the work and deliverables will be provided by of a joint collaboration between Cardiff University and the University of Manchester.

Planned Impact

See main proposal "The Radio Universe: astronomy and astrophysics at the Jodrell Bank Centre for Astrophysics 2014-2017"
PI: Prof Albert Zijlstra
Grant reference: ST/L000768/1
 
Description This project was originally awarded within the University of Manchester Consolidated Grant ST/L000768/1 led by Prof. A.Zijlstra. Later on Dr Pisano moved to Cardiff University taking with him part of the Project 3.2: "Large focal plane for future astronomical instruments" which was still shared with Dr B.Maffei at the Universities of Manchester.

The project was divided in three sections:
3.2.1) Large scale high performance waveguide component manufacture;
3.2.2) Large diameter mesh-based quasi-optical components;
3.2.3) Accurate RF characterisation and systematic effect study.
Dr Pisano role was to lead the RF modelling of the components for sections 1) and 2) and coordinate the manufacture of the components needed for section 2) and 3).

3.2.1) One of the goals was to identify a low-cost/mass-production technique to manufacture high quality waveguide components for millimetre-wave arrays. In collaboration with the SWISSto12 Company, which provides the 3D printing and metal coating manufacture, we have provided different designs of waveguide components to be realised in plastic via 3D printing/metallisation. We have successfully developed also a 600GHz corrugated horn based on stacked brass rings.

At the same time, triggered by another project for development of compact focal plane arrays (funded by ESA) we did divert our efforts toward a 'hybrid' focal plane solution based on a planar mesh-lens array. The novel idea was based on the mesh-filter technology. We have designed, manufactured and successfully tested a very compact and flat 7-pixel array that can replace the expensive electroformed corrugated horns and even the most recent 3D printed equivalent components. This additional route led to a completely novel solution that revealed to be even more cost-effective than the 3D printing one. The technology and the facilities required for this development were completely available within the Cardiff AIG group. This new idea has generated interest in our field and two new research collaborations with the Berkeley and Colorado Universities have started.

As planned, we have also investigated a low-cost/mass production technique for low-frequency waveguide components (~1.5GHz) using metallised foams. Cardiff has provided designs for waveguide transitions, polarisers and hybrid-mode horns. A waveguide transition was successfully realised at Manchester University together with a corrugated horn. The construction of a polariser in currently ongoing at Manchester.

2) The facilities required to build large diameter filters planned at Manchester University were delayed and not available at the time of the end of this project in Cardiff (it will last for another year in Manchester - 3/2017). In the meantime, in order to continue the activity the Cardiff Group, by using its own facilities, has designed and manufactured a large diameter dielectrically embedded multi-mesh filter (33cm diameter), a low-pass filter working around 100GHz, that will be RF tested (homogeneity) by the Manchester group during the last year of their project.

3) Within our plan to accurately characterise the beam produced/induced by quasi-optical components, we have carried out three dimensional measurements of orbital angular momentum vortexes created by a spiral-phase plate with unprecedented accuracy. The RF performance and systematics characterisation of the 7-pixel mesh-lens array provided by Cardiff was also carried out at Manchester.
Exploitation Route Within the development program of mesh-based quasi-optical components (3.2.2) we have designed and realised another novel device: an 'Artificial Magnetic Conductor' surface (AMC) working at millimetre wavelengths. A patent application was subsequently filed at Cardiff University (September 2015, GB1516322.3, Inventor: G. Pisano) relating to an: "Artificial magnetic conductor operating at mm and sub-mm wavelengths realised using metamaterials".

The device has many potential applications in the microwave engineering and telecommunication fields (absorbers, low-profile antennas, etc.). In order to explore this potential market, this development was further funded via an STFC Impact Acceleration Account: "AMC wide band absorbers". Within this grant we are now developing an application of the AMC device (a microwave absorber) and we are exploring the commercialisation routes for this work.
Sectors Aerospace, Defence and Marine,Electronics,Other
URL https://indico.in2p3.fr/event/13232/session/2/contribution/17/material/slides/0.pdf
 
Description As mentioned already, within the program (3.2.2) we have developed a new metamaterial-based device: an 'Artificial Magnetic Conductor' surface (AMC), or a 'magnetic mirror'. Further developments of this work had a strong impact outside academia. In the context of a European Space Agency (ESA) project, we have then realised a new application based on the AMC developed within this grant: an embedded reflective half-wave plate. The unprecedented performance of this device has been reported in the paper: "Multi-Octave Metamaterial Reflective Half-Wave Plate for Millimetre and Sub-Millimetre wave Applications," G. Pisano, et al., Applied Optics, 55, 10255-10262 (2016). The paper was highlighted by the Optical Society of America (OSA) which published a news release on our development with title "Magnetic Mirror Could Shed New Light on Gravitational Waves and the Early Universe" (13/12/2016). The news had a large impact on the web and the paper has been covered by several major media outlets (including Yahoo) and by the European Space Agency. On the 7/1/2017 we received a letter from OSA congratulating us for the attention that our paper received and also stating that the overall media coverage related to our article had a potential audience reach of 191.5 million worldwide. Here follow some of the web links: http://www.osa.org/en-us/about_osa/newsroom/news_releases/2016/magnetic_mirror_could_shed_new_light_on_gravitatio/ http://www.esa.int/Our_Activities/Space_Engineering_Technology/Magnetic_mirror_design_for_finding_evidence_of_primordial_gravitational_waves http://finance.yahoo.com/news/magnetic-mirror-could-shed-light-150000087.html http://www.astro.cardiff.ac.uk/newsandevents/?page=news_detail?ws=0218 http://www.media.inaf.it/2016/12/14/specchio-specchio-magnetico-delle-mie-brame/ http://www.inovacaotecnologica.com.br/noticias/noticia.php?artigo=espelho-magnetico-vai-detectar-ondas-gravitacionais-espaco&id=010130161227
First Year Of Impact 2016
Sector Aerospace, Defence and Marine,Other
Impact Types Cultural