The Internet of Things recognises the value of interconnecting vast numbers of physical objects equipped with sensors to enable process automation and new data applications. For a wide range of applications the sensors will be wireless and operate without a battery or internal power supply, reducing the cost and complexity of the sensor. Radiative radio frequency (RF) energy transfer is an attractive method to provide small amounts power to electronic devices over a range of a few meters and is already used in radio frequency identification (RFID) systems which are increasingly replacing barcodes. However, the power available at the sensor or tag is severely limited which has limited the range of sensor tags so far preventing effective wide area operation. This project seeks to address the limited range of passive wireless sensor tags, by considering for the first time a complete sensor network comprised of multiple sensors and a unified distributed interrogator network. Most RF power delivery systems are limited by reflections which occur in realistic environments. Here use of multiple antennas will allow the wireless channel (reflections) to be characterised and the transmitted signals optimised to mitigate the effects, increasing the RF power available at the sensor tag when it is required to collect a data sample, improving the performance of both digital and analog sensor tags. This will enable both more energy intensive sensor functions and wider operating areas with greater reliability opening up a range of applications where the performance of passive sensor tags has currently insufficient. With a wider operating area, a new problem of large populations of sensor tags simultaneously operating in the interrogation region will also be addressed. An application model will consider which sensors are required to operate with what duty cycle to ensure sufficient data is collected. This can be optimised by considering the mutual information of multiple sensors and also the channel information to select those sensors with the most favourable channels. Finally, the developed sensor tags and interrogator system will be built into a demonstrator for healthcare applications. This will both guide the development of the application model to cope with multiple different sensors with different power and duty cycle requirements, and also allow the system to be demonstrated to potential future collaborators (both academic and industrial) across various disciplines. We believe the potential impact in healthcare is significant due to the less intrusive nature of wireless sensing, less bulky sensors with no battery and the ability of sensors to be readily disposable at low cost.

This proposal seeks funding to create a Centre for Doctoral Training (CDT) in Connected Electronic and Photonic Systems (CEPS). Photonics has moved from a niche industry to being embedded in the majority of deployed systems, ranging from sensing, biophotonics and advanced manufacturing, through communications from the chip-to-chip to transcontinental scale, to display technologies, bringing higher resolution, lower power operation and enabling new ways of human-machine interaction. These advances have set the scene for a major change in commercialisation activity where electronics photonics and wireless converge in a wide range of information, sensing, communications, manufacturing and personal healthcare systems. Currently manufactured systems are realised by combining separately developed photonics, electronic and wireless components. This approach is labour intensive and requires many electrical interconnects as well as optical alignment on the micron scale. Devices are optimised separately and then brought together to meet systems specifications. Such an approach, although it has delivered remarkable results, not least the communications systems upon which the internet depends, limits the benefits that could come from systems-led design and the development of technologies for seamless integration of electronic photonics and wireless systems. To realise such connected systems requires researchers who have not only deep understanding of their specialist area, but also an excellent understanding across the fields of electronic photonics and wireless hardware and software. This proposal seeks to meet this important need, building upon the uniqueness and extent of the UCL and Cambridge research, where research activities are already focussing on higher levels of electronic, photonic and wireless integration; the convergence of wireless and optical communication systems; combined quantum and classical communication systems; the application of THz and optical low-latency connections in data centres; techniques for the low-cost roll-out of optical fibre to replace the copper network; the substitution of many conventional lighting products with photonic light sources and extensive application of photonics in medical diagnostics and personalised medicine. Many of these activities will increasingly rely on more advanced systems integration, and so the proposed CDT includes experts in electronic circuits, wireless systems and software. By drawing these complementary activities together, and building upon initial work towards this goal carried out within our previously funded CDT in Integrated Photonic and Electronic Systems, it is proposed to develop an advanced training programme to equip the next generation of very high calibre doctoral students with the required technical expertise, responsible innovation (RI), commercial and business skills to enable the £90 billion annual turnover UK electronics and photonics industry to create the closely integrated systems of the future. The CEPS CDT will provide a wide range of methods for learning for research students, well beyond that conventionally available, so that they can gain the required skills. In addition to conventional lectures and seminars, for example, there will be bespoke experimental coursework activities, reading clubs, roadmapping activities, responsible innovation (RI) studies, secondments to companies and other research laboratories and business planning courses. Connecting electronic and photonic systems is likely to expand the range of applications into which these technologies are deployed in other key sectors of the economy, such as industrial manufacturing, consumer electronics, data processing, defence, energy, engineering, security and medicine. As a result, a key feature of the CDT will be a developed awareness in its student cohorts of the breadth of opportunity available and the confidence that they can make strong impact thereon.

This proposal seeks funding to create a Centre for Doctoral Training (CDT) in Integrated Photonic and Electronic Systems. Photonics plays an increasing role in systems, ranging from sensing, biophotonics and manufacturing, through communications from the chip-to-chip to transcontinental scale, to the plethora of new screen and projection display technologies that have been developed, bringing higher resolution, lower power operation and enabling new ways of human-machine interaction. These advances have set the scene for a major change in commercialisation activity where photonics and electronics will converge in a wide range of information, sensing, communications, manufacturing and personal healthcare systems. Currently, systems are realised by combining separately developed photonic components, such as lasers and photodetectors with electronic circuits. This approach is labour intensive and requires many electrical interconnects as well as optical alignment on the micron scale. Devices are optimised separately and then brought together to meet systems specifications. Such an approach, although it has delivered remarkable results, not least the communications systems upon which the internet depends, limits the benefits that could come from the full integration of photonics with electronics and systems. To achieve such integration requires researchers who have not only deep understanding of their specialist area, but also an excellent understanding across the fields of electronic and photonic hardware and software. This proposal therefore seeks to meet this important need, building upon the uniqueness and extent of the UCL and Cambridge research, where research activities are already focussing on the direct monolithic integration of lasers with silicon electronics, new types of displays based on polymer and holographic projection technology, the application of photonic communications to computing, personal information systems and indeed consumer products (via board-to-board, chip to chip and later on-chip interconnects), the increased use of photonics in industrial processing and manufacture, techniques for the low-cost roll-out of optical fibre to replace the copper network, the substitution of many conventional lighting products with photonic light sources and extensive application of photonics in medical diagnostics and personalised medicine. Many of these activities will increasingly rely on more advanced electronic systems integration, and so the proposed CDT includes experts in electronic circuits, computer systems and software. By drawing these complementary activities together, and building upon initial work towards this goal carried out within our previously funded CDT in Photonic Systems Development, it is proposed to develop an advanced training programme to equip the next generation of very high calibre doctoral students with the required technical expertise, commercial and business skills, and thus provide innovation opportunities for the integration of photonic and electronics in new systems in the coming years. It should be stressed that the CDT will provide a wide range of methods for learning for research students, well beyond that conventionally available, so that they can gain the required skills. In addition to conventional lectures and seminars, for example, there will be bespoke experimental coursework activities, reading clubs, roadmapping activities, secondments to companies and other research laboratories and business planning courses. The integration of photonic and electronic systems is likely to widen the range of systems into which these technologies are deployed in other key sectors of the economy, such as printing, consumer electronics, computing, defence, energy, engineering, security and medicine. As a result, a key feature of the CDT will be a developed awareness in its student cohorts of the breadth of opportunity available and a confidence that they can make impact therein.