PhD Studentship: Coded Excitation Methodologies for Ultrasonic Testing Techniques, Exhibiting Poor Signal to Noise Performance

Closing Date
20 January 2022

More info

Project description

UT techniques suffer from poor SNR and low penetration when:

  • the material under inspection has non-ideal acoustic properties (e. g. plastics, composites, austenitic)
  • sensors due to environmental limitations are: using transduction materials with sub-par properties (high temperature) or limited in their maximum operating voltage (explosive environments)
  • frequency of acoustic wave requires increase

With UT, we include single element techniques, multi element phased array and synthetic beamforming techniques, along with guided acoustic wave techniques. TWI’s work has already shown, that coded excitation is a promising methodology, that can overcome all the above cases.

The first stage of research would be to theoretically and experimentally compare coded excitation methodologies with respect to:

  • Acoustic beam shape
  • Beam propagation
  • Acoustic signal penetration
  • SNR of processed signals
  • Spatial resolution
  • Waveguide requirements

Using tuned negative square pulse and Hann windowed sinusoidal pulse as comparison basis.

Theoretical work will include:

  • Tuned coded waveform generation
  • Ultrasonic transducer transfer function estimation
  • Investigation of the applicability of semi-analytical acoustic wave propagation models with coded excitations
  • FEA dynamic wave propagation

Semi-analytical and FEA tools exist at TWI.

Experimental work will include:

  • Experimental definition of ultrasonic transducer transfer function
  • PWM transducer drive to generate controllable sinusoidal signals
  • Identifying electronic circuit limitations
  • Receive signal processing (matching filters, auto-cross correlation)
  • Comparative feature extraction
  • Automation of experimental setups

The second stage of this research is to experimentally evaluate the usefulness of coded excitation on series of engineering applications, where UT is currently not possible or is severely limited.

We are looking for candidates with enthusiasm, multidisciplinary collaboration and tackling challenging problems through teamwork. Applicants should be of a high quality and exceptionally motivated. Experience with ultrasound non-destructive testing and essential experience in programming in Matlab would be advantages.

This is exciting opportunity for student to join TWI Technology Centre (Wales) and Centre for Efficiency and Performance Engineering (CEPE), led by Professor Len Gelman, a holder of two Rolls Royce Awards for Innovation.

TWI Technology Centre (Wales) specialises in the development and application of state-of-the-art non-destructive testing methods. Through applied research and development, we provide real-world solutions to inspection challenges across a broad range of industries.

The CEPE has strong record in applied research in the academic/industrial sectors. Application areas include vibration monitoring of complex electro-mechanical systems, advanced non-stationary signal processing, pattern recognition and multi-sensor fusion. These are applied to multiple industries, including power generation, automotive, aerospace and oil/gas.

If you wish to discuss details informally, please contact: Miles Weston, email: and Prof. Len Gelman, email:

For further information about this, please visit Research Degree Scholarships in Engineering – University of Huddersfield

Applications should include: Curriculum Vitae, two reference letters, degree transcripts to date and certificates of all relevant academic and/or any professional qualifications.

Please note: if you do not attach all the relevant documentation prior to the closing date, your application will not be considered.

Posted on 23rd November 2021 in Job Opportunities in Acoustics