Current interests

Srinath Rajogapal is currently working on optical methods for the acoustical realisation of Pascal for absolute calibration of hydrophones and development of secondary standard calibration methods using broadband acoustic pulses in the frequency range 100 kHz to 20 MHz. He is also involved in the development of measurement methods for ultrasonic output power based on buoyancy change, a form of calorimetry and solid-state pyroelectric technique. He is responsible for managing the medical ultrasound hydrophone calibration service covering frequencies in the range 100 kHz to 60 MHz.

Biography

Srinath received his BEng in Biomedical Engineering from Visvesvaraya Technological University, Belgaum, India, in 2002 and MRes at the Bioengineering Department from the University of Strathclyde, Glasgow, UK, in 2004. He started as a Research Physicist at Precision Acoustics Ltd, Dorchester. Whilst at Precision Acoustics he was responsible for their calibration service, software development for automating test and measurements, providing support in production and testing of hydrophones and auditing of internal processes to ISO 9001: 2000 quality standards. He joined NPL in 2007 and has since been active in the medical ultrasound group.

Committees

Srinath represents the UK on the International Electrotechnical Commission TC87/WG8 Ultrasonics - Field Measurements. He also serves as an NPL observer for the Ultrasound and Non-Ionising Radiation Special Interest Group of the Institute of Physics and Engineering in Medicine, UK.

Selected publications

• The buoyancy method - a potential new primary ultrasound power standard
  S. Rajagopal and A. Shaw
  Metrologia, 49 (3), pages 327-339 (2012)
• Systematic evaluation of a secondary method for measuring diagnostic-level medical ultrasound transducer output power based on a large-area pyroelectric sensor
  B. Zeqiri, G. Žauhar and S. Rajagopal
  Metrologia, 49 (3), pages 368-381 (2012)
• Inter-laboratory Comparison of HITU Power Measurement Methods and Capabilities
  K.V. Jenderka, G. Durando, B. Karaböce, S. Rajagopal and A. Shaw
  J. Phys.: Conf. Ser. 279 (2011)
• Instantaneous input electrical power measurements of HITU transducer
  B. Karaböcel, Y. Gülmezl, S. Rajagopal and A. Shaw
  J. Phys.: Conf. Ser. 279 (2011)
• A random phased array device for delivery of high intensity focused ultrasound
  J.W. Hand, A. Shaw, N. Sadhoo, S. Rajagopal, R.J. Dickinson and L.R. Gavrilo
  Physics in Medicine and Biology, 54 (19), pages 5675-5693 (2009)
• A Fabry-Perot fibre-optic hydrophone for the measurement of ultrasound induced temperature changes
  P. Morris, A. Hurrell, E. Zhang, S. Rajagopal and P. Beard
  Proc.-IEEE Ultrason. Symp., pages 536-539 (2006)

Contact details

Email: srinath.rajagopal@npl.co.uk
Tel: 020 8943 6696