LTCC‐based liquid metal tunable high‐Q notch filters for the emerging 5G communication systems

This joint PhD project is based at The University of Melbourne with a minimum 12 month stay at KU Leuven

Project title:  Versatile usage of liquid metals in emerging microwave technologies

Project description
The current approaches for implementation of tunable high‐Q notch filters fail to concurrently address the compact size, high‐Q and strong attenuation, and frequency tunability challenges.

Research objectives
The research objectives are three‐fold:

  1. To investigate and model various resonator topologies to produce high‐Q and strong in‐band attenuation using liquid metals;
  2. To explore possible solutions to achieve a fast tunable/reconfigurable notch filter using liquid metals and LTCC (Low Temperature Co‐fired Ceramic) technology;
  3. To analyse and model a high order tunable/reconfigurable filter using liquid metal with minimum insertion loss.

This PhD project aims to investigate and design a compact and tunable/reconfigurable notch filter using LTCC (Low Temperature Co‐fired Ceramic) fabrication technology and liquid metals for 5G applications. 5G transceivers will be required to support a large number of applications with diverse requirements in terms of frequency and bandwidth. These requirements necessitate multi‐standard and multi‐band communication systems with tuning and reconfiguration capabilities.

The proposed filter will be based on these requirements and will be integrated with other microwave devices in the transceiver. Existing techniques of implementing a notch filter are either bulky, have a high insertion loss or lack high attenuation within the stopband of the filter. The LTTC fabrication technique will provide a compact filter with very high‐Q, achieving low loss and strong attenuation in the frequency band of interest where the rejection of interfering signal is an essential part of the transceiver. The filter can be tuned or reconfigured by utilising a liquid metal, such as Galinstan, in microchannels.

Initially, a high‐Q resonator with a fast tuning/reconfiguring response will be investigated, and then a high order filter will be designed based on the initial resonator. This PhD research builds on the complementary expertise on fabrication using LTCC technology and liquid metals at the University of Melbourne, and the knowledge on (tunable/reconfigurable) filter modelling at KU Leuven.

The project will be complemented by the project on Self‐healing flexible biosensors for microwave dielectric spectroscopy and the collaboration will ensure a successful completion of the project.

Supervision team:

Principal Investigators (PIs)

Professor Stan Skafidas (The University of Melbourne)
Professor Dr Dominique Schreurs (KU Leuven)

Co-Principal Investigators (co-PIs)

Professor Robin Evans (The University of Melbourne)
Professor Dr Bart Nauwelaers (KU Leuven)