Photonic and Microwave Engineering
School of ITEE

Research Focus

Our  research can be broadly grouped into three focus areas:

Communications & Signal Processing
  • Communications & Signal Processing
  • Passive & active radar signal processing
  • Space surveillance
  • Signal processing for Electronic Warfare
  • Coding & information theory
  • Detection & estimation theory
  • Sensor fusion
Imaging Systems
  • Portable microwave system for imaging and monitoring of the human body 
  • Microwave system for pulmonary oedema detection
  • Microwave imaging system for brain stroke detection and classification
  • Differential imaging system for breast cancer detection
  • Microwave imaging system for lung cancer detection
  •  Pleural effusion microwave-based detection system
  • Design of planar microwave devices (filters, couplers, power dividers, phase shifters) and sub-systems for wideband applications (microwave medical imaging, and telecommunications)
  • Wideband antennas for biomedical applications
  • Reconfigurable and switched-beam antenna arrays for satellite and mobile communications
  • Compact radar systems for imaging and surveillance
  • Compact, planar multi-band antennas for mobile applications
  • Millimetre wave beamforming systems for 5G mobiles
Self mixing Laser Sensors

The self-mixing phenomenon occurs when the laser beam is partially reflected from an external target and injected back into the laser cavity. The reflected light interferes or mixes with the light inside the laser cavity and produces variations to the laser operating parameters. This phenomenon allows the laser to be used as an interfeometric sensor incorporating the light source and the interferometer in one device, thus significantly reducing the cost and complexity of the sensing system.

Recent developments in the design of semiconductor laser sources at near-infrared, mid-infrared and terahertz frequencies, coupled with the self-mixing approach to signal detection and the integration of these into imaging and sensing platforms, provide a way forward in the design of the next generation of detection systems. The team is exploiting novel laser sources and the self-mixing interferometry for non-invasive sensing in biomedicine and biochemistry.

Some of our current projects (based on self-mixing interferometry) include:

  • Biomedical imaging sensors based on two-dimensional arrays of Vertical-Cavity Surface-Emitting Lasers (VCSELS).
  • Embedded flow sensors in microfluidic systems
  • Quantification and imaging of skin blood perfusion
  • Optical measurement of surface biopotentials such as the electrocardiograph (EKG)
  • Development of self-mixing techniques with Terahertz quantum-cascade-lasers