Our Mission
About Microwave Research
To achieve self-reliance in strategic microwave tube technologies for India by pioneering the indigenous design, development, and fabrication of critical vacuum electronic devices (VEDs) including helix and coupled-cavity travelling wave tubes, coaxial magnetrons, multi-beam klystrons, and microwave power modules for radar, electronic warfare, and satellite communication systems. Through cutting-edge research in electron optics, advanced analytical modelling, multi-physics simulation, and CAD tools such as PIERCE and LKOBRA, we strive to train and mentor the next generation of scientists and engineers, foster collaboration with academia and defence research organisations, and contribute to India's technological sovereignty in high-power microwave sources and vacuum microelectronics.
R and D Achievements: Microwave Vacuum Electronic Devices
I led research groups and students at CSIR-CEERI, Pilani and MTRDC and directly contributed to research, design and indigenous development following Vacuum Electronic Devices (VED).
- Travelling-wave Tubes (TWTs)
- Pulsed and CW medium-high Power Helix TWTs
Experimental High-Power Microwave Devices
- Virtual Cathode Oscillator (Vircator): Axial, and tunable cavity type
- Relativistic Magnetron with Diffraction Output
- Magnetically insulated line Oscillator (MILO)
- High-voltage pulse power System with Blum-line (500kV)
Component & Sub-assembly Technology
Electron Guns: Convergent gun, control / shadow-gridded guns, multi-beam gun, field emission gun, MIG gun
Tungsten Dispenser Cathodes: B-, M-, MM-type Ferroelectric Cathodes
Field Emission Cathodes: S-tip array, Vertically aligned MW-CNT
Microwave-vacuum windows: Circular pillbox window, rectangular resonant window, coaxial window and input/output couplers for helix- & coupled-cavity TWTs
- Thermal, structural and coupled analysis using finite element codes
- Multi-physics and particle-in-cell simulation of complete MWTs – helix TWT, CC-TWT, EIK, BWO, Vircator, relativistic magnetron and multi-beam klystron.
Theoretical Analysis, Modelling & Simulation
His contributions and guidance led to the development of analytical modelling and CAD tools/methodology for microwave circuits and electron optics for MWTs:
Helix slow-wave Structures (SWS):
- Analytical models: for dispersion & Impedance characteristics of vane/segment-loaded helix SWS, sheath helix and tape helix and ring-loop SWS
- Anisotropic dielectric/chiral dielectric-supported helix SWS
- Multi-dispersion/phase velocity types in helix SWS for multi-octave broadband microwave/mm-wave TWTs
- Analysis of thin film attenuators, severs, mandrel line resonant attenuators and helix conductivity loss in millimeter-wave helical SWS
- Instability Analysis in SWS: p-Mode stopband in an asymmetric helical SWS and BWO start oscillation condition
- Formulation for plasma frequency reduction factor
- Artificial neural networks for optimization of tube design
Coupled-cavity Slow-wave structures
- Analysis of Circular Corrugated Waveguides Using Coupled Integral Equation Technique
- Improved Equivalent Circuit Model of fundamental backward-wave CC-SWS
- Models of double-slot shaped ferrule-coupled-cavity, interdigital circuit CC-SWS
- Folded-waveguide and dielectric-supported Meander-Line SWS for mm-wave TWTs
- SWS Models: double-slot shaped ferrule-coupled cavity, inter-digital circuit, folded-waveguide,
- Coaxial and waveguide transmission lines, cavity resonators, and microwave-vacuum windows.
Electron-Optical Systems for Linear Beam Devices: Electron Guns & Multi-Satge Depressed Collctors
- PIERCE: A 2.5-D 9-point-FDM Electron Optics code for electron guns, depressed collectors, electrostatic- and magnetic-focusing, including secondary electron and ion effects
- 3-D Package LKOBRA: for simulation of depressed collectors for space TWTs (based on KOBRA3-INP) Codes for magnetic focusing systems for electrons
R and D Management
Welcome Dr Lalit Kumar, your trusted partner in business and management consulting
- I have managed large research groups and evolved a full-fledged microwave tube R&D laboratory (Est. in the 1990s) for almost two from 1996 onwards. My passion for vacuum electronics resulted in a steady growth of the MVED R&D in the country in all areas: number of projects, overall funding, transfer of technology – leading to production – IPR output, laboratory space and facilities, and scientific and technical manpower. Strong emphasis was laid on enhancing the competence of the manpower and empowerment by mentoring, hands-on training, continuing education and leadership.
- Led a team of young scientists & technologists to strengthen and optimise existing technological processes and introduced new processes to reduce the development time and cost of microwave tube fabrication from raw materials to deliverable tubes. Created a modern integrated facility for microwave tubes. Implemented the ISO-9001:2000/2008/2015. Quality management system for projects, processes & facilities; established NDT and environmental testing facilities. Launched and managed collaborative projects with Indian and foreign partners. Promoted basic research in the area by funding collaborative projects at academic institutions and sister laboratories, organising national/international conferences, special courses, exchange visits, research contracts and invited lecturers. Initiated several projects on microwave tubes, power modules, transmitters and dispenser cathodes Technology was transferred to industry after full qualification certification by QA agencies, and production was established for some of the completed projects. Launched research in frontier areas, such as HPM sources, gyrotron devices and vacuum microelectronic devices and thermal management for high-average-power devices.
