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Title: Low-cost antennas and systems for next generation wireless communications
Author: Kgwadi, Monageng
ISNI:       0000 0004 6421 5588
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 2017
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This work presents a study of low-cost antennas and communication systems to support the burgeoning demand for bandwidth in the next generation wireless communications and networks (5G) and/or Internet of Things (IoT). The work was divided into three different fields all aimed at low-cost solutions of enabling next generation networks (5G) and IoT. The first part of the study involves study of low-cost fabrication of antennas and radio frequency (RF) guided wave structures up to 10 GHz using the thermal transfer printing (TTP) technique on renewable, light weight, flexible and low-cost substrates. The thermal transfer printing method for electronics was characterised from DC to 10 GHz and benchmarked for performance against inkjet printing technique which is an established technique for printed electronics. TTP achieved similar or better read range to inkjet printed radio frequency identification (RFID) antennas that were used in this study. Applications of the TTP method in IoT taking advantage of its speed and low cost were demonstrated by; producing on-demand antennas and/or rapid prototyping electronic designs, using off the shelf components to build a frequency agile antenna, and an ultra wideband antenna (UWB) for low power short range communications. The second part involves design and optimisation of a multi-port driven (MPD) slot-ring antenna for purposes of integration with resonant tunnelling diode (RTD) oscillators for millimetre-wave communications. The optimised structure managed airside radiation without the use of bulky lenses and achieved directivity of 10.8 dBi. The concept of the slot-ring with a backing ground plane was experimentally verified by a fabricated antenna for 5 GHz operation showing the expected performance. The third part is an experimental study of modulating RTD oscillators to deter- mine and improve achievable modulation bandwidth to meet 5G demands. Wireless transceiver systems at 28-40 GHz and 240 GHz were build using combinations of horn antennas, quasi-optical Schottky barrier diode detectors and some off-line signal processing. The modulation bandwidth of the oscillators were found to be limited to 300 Mbps and 16 Mbps for the 28-40 GHz oscillators and 220-300 GHz oscillators respectively due to oscillators being optimised for high power output instead of high modulation rates. Recommendations are made to improve the modulation datarate of these oscillators in order to meet the 5G datarate targets.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: TK Electrical engineering. Electronics Nuclear engineering