|Investigation and demonstration of the industrial relevance of new type of microwave components and subsystems based on ceramic ferroelectrics with electrically tuneable dielectric permittivity is proposed.
Two subsystem level applications are considered to demonstrate the advantages of the new technology:
i) ferroelectric plate (lens) for microwave beam-scanning, equivalent to a complex phased array antenna, and
ii) reconfigurable/adaptable phased array antenna in the form of multi-component assembly based on tuneable components.
These cost effective antennas are supposed for applications in microwave communications systems.
Objectives will be achieved by sub-system analysis and producing requirements to components and materials, development of bulk and thick film ferroelectic ceramics and devices based on them.
Main project outputs:
i) New industrial applications targeted compositions of electrically controllable ceramic ferroelectrics
ii) Device/subsystem demonstrators
iii) Design methods
iv) Physical models of ferroelectrics at microwave frequencies.
This work proposes the investigation and demonstration of the industrial relevance of new type of microwave components and system architectures based on ceramic ferroelectrics with electrically tuneable dielectric permittivity. The materials are based on oxide ferroelectrics (e.g. Titanates) in the form of bulk and thick film ceramics. Two system level applications are considered to demonstrate the advantages of the new technology. One is a ferroelectric plate (lens) performing beam-scanning function, equivalent to a complex phased array antenna. The second is a reconfigurable/adaptable phased array antenna in the form of multi-component assembly, where all components are electrically controlled and based on ferroelectric materials manufactured in single or similar technologies. These cost effective antennas are supposed for radio link, and similar, applications in advanced microwave communications systems.
Electrically tunable ferroelectic components enable development of new low cost subsystem architectures including high performance flexible phased array antennas. For these applications, the development of new ceramics with higher tuneability (electric field dependent permittivity) and lower losses with industrially relevant parameters is a challenging task. The problems to be addressed are the temperature stability, linearity of permittivity-electric d field relationship (dependence), hysteresis effects, reduction of the leakage currents, tuning voltages and aging under DC field. Tuneable ceramics will be tested in device demonstrators of industrial relevance. New approaches in the theory of ferroelectricity, fabrication processes, device design/modelling and system ideology are needed to achieve the objectives. The consortium is complementary and involves organisations that work in ceramics (ferroelectric) science and engineering, device designs and microwave systems (end user of the materials end devices). Initially the material focused upon will be Barium Strontium Titanates. Alternative ferroelectric compositions will be investigated. Bulk (two different) and thick film (two different) processing routes will be developed, each of which may offer advantages in performance, cost or compatibility with microwave device technology.
The work can be split into the following major areas:
i) Specifications of components and materials based on subsystem/system analysis;
ii) Material development, including a proper choice of ceramic's composition and ceramic processing routes to achieve the required dielectric properties;
iii) Components (beam scanning plate, tuneable phase shifters, power splitters, matching networks, filters and radiators) design, fabrication and testing.
The main outputs of the project are:
i) New compositions of electrically controllable ceramic ferroelectrics with industrial (market) application targeted parameters and their fabrication processes
ii) device demonstrators, and
iii) methodology for the design of microwave devices based on such ferroelectric materials.
The example devices are chosen for application in two new types of antennas operating at frequencies above 20 GHz, where the potential of the ferroelectric technology is fully demonstrated. However, the applications of these materials and devices are wide ranging (microwave systems, information technology, sensors).
Three major milestones are planned, since the devices are developed in parallel with new materials. Prototype development using initial ceramics will be completed at the end of first year. Development of ceramics and devices with improved performances will be completed at the end of second year, considering new non-BST ceramics. Last year will further optimise ceramics and devices and evaluate the technology. Industrial relevance of the materials and devices will be monitored continuously.
Expected results: new knowledge, materials, devices, and subsystem level demonstrators.