Public defence in Radio Engineering, M.Sc. Tauseef Siddiqui

M.Sc. Tauseef Siddiqui will defend the thesis "Novel Modulated Backscattered Communication Techniques for Transponder Based on Multiple Antennas" on 18 May 2022 at 12 (EET) in Aalto University School of Electrical Engineering, Department of Electronics and Nanoengineering, in lecture hall AS1, Maarintie 8, Espoo.

Opponent: Prof. Will Whittow, Loughborough University, UK
Supervisor: Prof. Ville Viikari, Aalto University School of Electrical Engineering, Department of Electronics and Nanoengineering

Thesis available for public display at: https://aaltodoc.aalto.fi/doc_public/eonly/riiputus/
Doctoral theses in the School of Electrical Engineering: https://aaltodoc.aalto.fi/handle/123456789/53

Press release:

The number of connected Internet of Things (IoT) devices are estimated to cross 25 billion by the year 2030. The increased deployment of IoT devices in various aspects of our lives has resulted in providing us with substantial benefits such as enhanced quality of life and task automation. As a result of this, antennas for IoT devices continue to have stricter performance requirements with the advancement of wireless communication technology. Recently, a novel backscattering technique, referred to as ambient backscatter communication systems (ABCSs), has attracted increasing attention. Unlike conventional backscatter, ABCS does not generate radio wave itself but takes benefit of already available radio signals from ambient sources such as radio broadcast transmitters, Bluetooth, television towers, cellular towers, and Wi-Fi access points. A backscatter device (transponder) will produce a modulated reflection of existing signals, resulting in fluctuation in the signal phase and/or amplitude at a close by receiver. Thus, ABCSs is more energy- and spectrum-efficient. ABCSs is also one of the candidate solutions for the 6G-enabled IoT networks. The purpose of the research presented in this dissertation is to provide transponder antenna solutions for enhanced performance in backscatter communication techniques that could be used for future IoT applications. The concept of a transponder that can independently perform amplitude and phase modulation is presented. Such a modulator enables modulation schemes that necessitate multiple states. In addition, the research focuses on design and implementation of a broadband transponder implemented using frequency-reconfigurable cluster antenna. The approach eliminates the typically needed tunning components and uses mutual coupling in its advantage. Current state-of-the-art transponders utilizing the modulated backscattering principle rely on fixed antennas, whose impedance cannot be reconfigured. Broadband transponder in this scenario can utilize the ambient wave efficiently. Furthermore, a novel concept of beam-steerable transponder based on antenna array and phased modulators is presented for monostatic and bistatic configurations. The RF sources in ABCSs are unpredictable regarding transmission powers and locations. Therefore, effective use of RF sources requires the transponder to tune its operation, where the highest ambient power is available. The receive and transmit beams can be controlled by adjusting modulator delays.

Contact information of doctoral candidate: