CW operation of 94GHz Gyro-TWA for telecommunications applications

Lead Research Organisation: University of Strathclyde
Department Name: Physics


This proposal will develop the world's highest power (kW), broadest instantaneous bandwidth, frequency agile amplifiers operating in the mm-wave/terahertz range. The gyro-amplifiers offers a unique opportunity to fill a long standing gap in the generation of high power coherent millimetre and sub millimetre wave radiation with its promise of amplification with an unprecedented 20% instantaneous bandwidth and an unrivalled power of 5kW at 94 GHz. Building on the recent success of "W He et al PRL 2013, 110, art 165101, 2013", the mm/sub-mm wave gyro-TWA will enable a paradigm shift in what is achievable for a ground based, cellular telecommunications network by providing tera-bit data rates. This is possible due to the fact that the wireless gyro-TWA operating at sub-THz frequencies does not need to use opto-electronic components currently limiting data rates of optical schemes.

Another major area of development is the possibility of exploiting the world leading gyro-TWA to be used in Electron Paramagnetic Resonance (EPR) and Dynamic Nuclear Polarisation (DNP) spectroscopy which is currently hampered by the lack of high power sources and especially broadband amplifiers of terahertz radiation.

In addition the gyro-TWA would be an ideal source for cloud profiling radar and the detection of atmospheric pollutants because the atmospheric absorption, penetration and scattering losses, practical stand-off systems require considerable power, typically hundreds of watts. Other applications include high frequency long range security imaging, space situational awareness (detecting space debris), terrain mapping (volcano monitoring), radar and long range, high bandwidth, line of sight communications and real time video-rate detection of hidden explosives and illegal drugs.
Description The successful completion of this research objectives of this project has opened up opportunities for future exploitation of the world leading high power (3kW) broadband (20%) mm and sub mm-wave amplifiers for space object identification radar and satellite uplink applications
Exploitation Route Currently there are no high power (kw), broadband (10% to 20%) amplifiers operating in the 90GHz to 110GHz, 230GHz to 290GHz, 360GHz to 440GHz frequency range. Successful completion of the research objectives of this project enable a follow on Genvolt DC power supply to be acquired. This will enable high power continuous wave (kw) broad bandwidth (20%) wireless communication where the bandwidth in the hundered of GHz range enables multiples of tens of GBytes per second data rate communication. It also will enable high duty cycle operation of the gryo-TWA an essential requirement for Space Object identification ground based radar
Sectors Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software),Pharmaceuticals and Medical Biotechnology

Description A Gyrotron Travelling Wave Amplifier (gyro-TWA) is a new class of high power, wideband, fast-wave, millimetre wave amplifier which achieved a ten-fold increase in available bandwidth and a three-fold increase in available peak power over conventional slow-wave vacuum electron devices such as Extended Interaction Klystron (EIK) amplifiers. The fast wave mm-wave gyrotron travelling wave amplifier (gyro-TWA) developed at the University of Strathclyde had a 30 times higher power-bandwidth performance than any competing devices with an unmatched 3dB instantaneous frequency bandwidth (IFB) of 10% and is uniquely positioned to fill the "THz gap". A low duty cycle (1Hz), pulsed 4.3 kW, 38 dB gain mm-wave amplifier operated at a power of 4.3 kW with an IFB of 10 GHz (90 - 110 GHz). The mm-wave gyro-TWA was developed by Dr. Craig Donaldson, Dr. Colin Whyte and Dr. Liang Zhang and a team of researchers in the Atoms, Beams and Plasmas research Group in the Department of Physics, University of Strathclyde working in collaboration with project partners TMD Ltd and is being developed for mm-wave radar being designed by Dr. Duncan Robertson of the School of Physics and Astronomy at the University of St. Andrews.
First Year Of Impact 2019
Sector Aerospace, Defence and Marine
Impact Types Economic

Description DC power supply to drive W-band gyrotron travelling wave amplifier for satellite uplink and wireless communication applications (://
Amount £141,042 (GBP)
Funding ID ST/T003227/1 
Organisation Science and Technologies Facilities Council (STFC) 
Sector Public
Country United Kingdom
Start 11/2019 
End 03/2020
Description High power, wideband millimetre wave source for space object identification (
Amount £198,000 (GBP)
Funding ID Pi Dr. Colin G. Whyte 
Organisation Defence Science & Technology Laboratory (DSTL) 
Sector Public
Country United Kingdom
Start 09/2019 
End 08/2020
Title Data for: "Amplification of Frequency-Swept Signals in a W-Band Gyrotron Travelling Wave Amplifier" 
Description This dataset contains the experimental measurement data published on paper "Amplification of Frequency-Swept Signals in a W-Band Gyrotron Travelling Wave Amplifier", which is partially supported by EPSRC. The data files are recorded by using Keysight VSA software 89600, which can be downloaded from The data files recorded the beam voltage signals as well as the microwave signals when the gyro-TWA was driven by a CW signal and a chirp signal. Data embargo until 01/01/19 due to commercial constraints 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
Title W-band gyro-TWA 
Description This dataset contain files in OPJ formats which can be opened by data processing software ORIGIN, and WFM file format. It is created by Tektronic oscilloscope and it can be open by WAVESTAR FOR OSCILLOSCOPES. This data is for paper "Broadband Amplification of Low-Terahertz Signals Using Axis-Encircling Electrons in a Helically Corrugated Interaction Region" that been published in Physical review letter. 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
Description Horizon 2020 project CompactLight 
Organisation European Organization for Nuclear Research (CERN)
Country Switzerland 
Sector Academic/University 
PI Contribution Linear theory, non-linear theory and Particle-In-Cell simulations were used to design a three cavity 36GHz gyro-klystron of gain 39dB that is capable of producing 3.2MW of power corresponding to an efficiency of 43% at a PRF of 1kHz. Analysis of the phase stability of the amplifier found that 0.34 degree phase stability can be achieved for a variation in modulator voltage of 0.01%. The 36GHz gyro-klystron designed was compared to previously published gyro-klystron experiments. It was concluded that the 36GHz gyro-klystron when driven by a K100 (150kV, 50A) Scandinova modulator was a viable power source for a high-harmonic lineariser in a soft and hard X-ray Free Electron Laser. The high harmonic lineariser is required to mitigate unavoidable nonlinearities in the FELs electron bunch's energy profile introduced by the Linac accelerating fields.
Collaborator Contribution H2020 project CompactLight is a collaborative project to design a hard X-ray FEL facility beyond today's state of the art, using the latest concepts for bright electron photo injectors, very high-gradient X-band structures operating at 12 GHz, and innovative compact short-period undulators. Compared with existing facilities, the CompactLight design focused on i. benefiting from a lower electron beam energy, due to the enhanced undulator performance, ii. being significantly more compact, as a consequence of the lower beam energy and the high gradient of the X-band structures, iii. being more efficient with less power consumption, as a consequence of the lower energy and the use of higher frequency structures. Project partners consisted of 24 world-leading institutes across Europe and beyond contributing to the 3 objectives above: disseminating X-band technology as a new standard for accelerator-based facilities and advance undulators for the next generation of compact soft and hard X-ray FELs.
Impact During the past decades Synchrotron Radiation facilities have seen an impetuous growth as a fundamental tool for the study of materials in a wide spectrum of sciences, technologies, and applications. The latest generation of light sources, the Free Electron Lasers, capable of delivering high-intensity photon beams of unprecedented brilliance and quality, provide a substantially novel way to probe matter and have very high, largely unexplored, potential for science and innovation. Currently, the FELs operating in EU are three, FERMI, FLASH and FLASH II, operating in the soft X-ray range and two are under commissioning, SwissFEL and EuroXFEL, which will operate in the hard X-ray scale. While most of the worldwide existing FELs use conventional normal conducting 3 GHz S-band linacs, others use newer designs based on 6 GHz C-band technology, increasing the accelerating gradient with an overall reduction of the linac length and cost. CompactLight is multi-disciplinary gathering the world-leading experts in these domains, to achieve two objectives: disseminate X-band technology and associated sub-systems such as Ka-band linearisers as a new standard for accelerator-based facilities and advance undulators to the next generation of compact photon sources, with the aim of facilitating the widespread development of X-ray FEL facilities across and beyond Europe by making them more affordable to build and to operate.
Start Year 2018
Description National Vacuum Electronics Conference (NVEC) 2019 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact Results from the sheet electron beam pseudospark project was presented at the National Vacuum Electronics Conference 2019 held in the Technology and innovation Centre, University of Strathclyde on the 13th of November 2019
Year(s) Of Engagement Activity 2019
Description Talk at Microwave Technology and Techniques Workshop at the European Space Agency, Noordwijk, The Netherlands 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Present an overview of the performance of the 3.4kW, 91GHz to 96GHz Gyro-TWA to satellite experts to show the unique performance of the gyro-TWA for Space Object Identification radar.
Year(s) Of Engagement Activity 2019