Section News

IEEE Milestone Award Event | Development of the Cavity Magnetron, 1939-1941

In 1939, at the start of the war, there was a need to efficiently achieve higher power microwave energy to enable the advance from land based into airborne radar.  Working at Birmingham in 1940, John Randall and Harry Boot produced the first working magnetron incorporating their novel resonant cavity design, which enabled the generation of hundreds of Watts of power at 10 cm wavelength.

Subsequently the engineers at the General Electric Company (GEC) in Wembley, re-engineered this device for mass production, enabling it to generate well over a kilowatt of pulsed power. These high-power microwave pulses could then be transmitted from an antenna only centimetres long, reducing the size of practical radar systems and improving the resolution of targets. This enabled the realisation of British and American long-range night-fighter and anti-submarine airborne radar systems.

Wartime Britain was unable to produce the devices in sufficient volume so the Tizard Mission offered the design to the Americans in September 1940. This led to the establishment of the Massachusetts Institute of Technology Radiation Lab and mass production of the Cavity Magnetron in the US.

On 4th June 2024, we celebrated the IEEE Milestone Award that recognises the development of the cavity magnetron by J Randall & H Boot & J Sawers at University of Birmingham in 1939.

On the previous evening, invited guests and organisers attended a celebration Milestone dinner at the Edgbaston Park Hotel.

The morning session consisted of several introductory presentations leading up to the plaque unveiling.

  • Welcome by the University of Birmingham Professor Adam Tickell (Vice Chancellor, University of Birmingham)
  • The IEEE and the importance of preserving the history of Electrical Engineering Dr Thomas Coughlin (IEEE President)
  • The IEEE Foundation and its support for the History Centre Professor Sarah Spurgeon (UCL and IEEE Foundation Board member)
  • The IEEE Milestone Program Professor David Michelson (Chair, IEEE History Committee)
  • This milestone on the generation of high power microwave energy Professor Peter Grant (University of Edinburgh)
  • The International importance of these developments Dr Tim Hall (MIT Lincoln Laboratory)
  • Unveiling of the Milestone plaque Professor Adam Tickell (Vice Chancellor, University of Birmingham) with Dr Thomas Coughlin (IEEE President)
  • Closure of the session followed by buffet lunch Rod Muttram (IEEE UK&I Industry liaison and LMAG)

The plaque unveiling was performed by IEEE President Dr Thomas Coughlin and Prof Adam Tickell, Vice Chancellor, University of Birmingham in the Poynting Building at the University of Birmingham, close to where the plaque will be permanently sited.

The unveiling was followed by a symposium celebrating the development of the Cavity Magnetron, the first device which was able to generate sufficient microwave energy to permit the realisation of airborne radar systems for ground mapping and submarine detection.

Chair: Professor Charles Turner (Emeritus Professor of Electrical Engineering, King’s College London)

  • 1.00 pm Early radar developments up to 1939 Professor Hugh Griffiths (University College London)
  • 1.30 pm The British development of the Cavity Magnetron Professor Peter Grant (University of Edinburgh)
  • 2.00 pm American Airborne Radar development at the MIT Radiation Laboratory Dr Mohamed Abouzhara (MIT Lincoln Laboratory)
  • 2.30 pm Canadian microwave radar projects in WW2 Professor David Michelson (University of British Columbia, Canada)
  • 3.00 pm British Airborne Radar Development in WW2 Professor Simon Watts (University College London and formerly Thales)
  • 3.30 pm From the Cavity Magnetron to Multi-function RF systems Dr Iain Scott (Leonardo)
  • 4.00 pm Current Birmingham radar research Dr Professor Marco Martorella (University of Birmingham)
  • 4.30 pm Closure of the seminar followed by wine reception Professor Izzet Kale (Immediate Past Chair, UK and Ireland Section) and Professor William Chaplin (Head Birmingham School of Physics & Astronomy)