Centre for Advanced Electronics

Join us for the annual CAE Lecture from Emeritus Professor Peter Grant OBE FREng FRSE FIEEE, University of Edinburgh.

Microwave energy generation advances which enabled the development of WW2 airborne radar

Following the independent development of radar in many countries from 1934-9 there was a need to efficiently achieve high power microwave energy to enable the transition from land based into airborne radar. John Randall and Harry Boot at the University of Birmingham produced, in February 1940, their cavity magnetron design which enabled, for the first time, the generation of hundreds of Watts of power at 10 cm wavelength. Shortly afterwards Eric Megaw with engineers at GEC, Wembley, further engineered this design, with assistance from French researchers, to generate well over a kilowatt of pulsed power. Subsequent innovations from James Sayers at Birmingham stabilised the output frequency. These high-power microwave pulses could be transmitted from an antenna only cm long, reducing the size and improving the system resolution enabling the realisation of long-range night-fighter, anti-submarine and high precision bomb aiming radar systems.

As Britain could not mass-produce these cavity magnetrons during the war, Winston Churchill agreed that Sir Henry Tizard should offer this magnetron design to the Americans in exchange for financial and industrial help. A 10 kW device, built at GEC, was taken to America on the Tizard Mission in September 1940. This initiated the formation of the Radiation Laboratory at MIT and the British and American cavity magnetron designs were immediately adopted for mass production to enhance the Allied wartime operational capability of airborne radar systems.

The presentation will feature cavity magnetron microwave radars as used in naval corvettes, B17 flying fortress bombers as well as the British H2S radar. The talk will review the post-war recognition for these inventors.

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About the Speaker: Emeritus Professor Peter Grant OBE FREng FRSE FIEEE

In 2002 Peter Grant served as first head of the School of Engineering at The University of Edinburgh where he was also appointed as the 8th Regius Professor of Engineering. After graduating from the Heriot Watt he held positions in industry at Plessey and Hughes Microelectronics before joining the University of Edinburgh in 1971. There he researched in analogue and digital signal processing on correlators, adaptive filters, nonlinear system identification, smart antennae and energy efficient processor designs which were applied predominantly to enhance the performance of wireless communication systems.

 He was awarded, in 2004, the 82nd Faraday Medal from the then Institution of Electrical Engineers and was elected in 2007 as one of the first four fellows of the European Association for Signal Processing (EURASIP), having served there as President 2000-02.  He holds Fellowships from: IEEE; Royal Academy of Engineering; and the Royal Society of Edinburgh. In 2009 he was made an officer of the order of the British Empire (OBE) in the Queen’s birthday honours list.  His many engineering contributions have been recognised by Honorary Doctorate awards from Heriot Watt, Edinburgh and Napier Universities.

First published: 17 March 2026