Asian Journal of Physics Vol 32, Nos 9 – 12 (2023) 671-680

Development of an X-band microwave power module for airborne radar

K Mirjitha, Tapas Ranjan Swaina, Talur Chanakyaa, Raja Ramana Raoa, U V Chandramoulia, Md Rezaul Karimb, Jyotirmoy Konerb, S Senthil Kumarb, P Sidharthana, and Subrata Kumar Dattaa
aMicrowave Tube Research & Development Centre (MTRDC), Bangalore-560 013, India
bMicrowave Tubes Division, Bharat Electronics Limited (BEL), Bangalore- 560 013, India
Dedicated to Prof B N Basu

A narrow band microwave power module (MPM) operating in X-band was developed that delivers 175W of peak output power with 52.5 dB nominal gain up to 20% duty cycle of operation. This MPM has a solid-state power amplifier (SSPA) as the driver amplifier followed by a power booster mini-travelling wave tube (mini-TWT) for achieving superior efficiency and noise performances. The MPM is packaged in an aluminium enclosure within a volume of 270 mm × 240 mm ×110 mm and weighs about 6.3 kg. The enclosure is openable in two halves to maximize the surface area available for accommodating the RF Section and the Electronic Power Conditioner (EPC). This concept of two-halves configuration enables the MPM operation without any cooling mechanism for a duration lasting up to 5 minutes. The compact electronic power conditioner incorporates high frequency switched series resonant power converter for catering the high voltage requirements of the mini-TWT. The high voltage section has a planar transformer for achieving superior efficiency and high power conversion density. The RF Section consists of both passive and active components which delivers the required output power and provides a sample signal for both protection and power monitoring purposes. The TWT used in the RF chain consists of Pierce-type electron gun, negatively dispersive slow wave structure (SWS), single stage depressed collector, and periodic permanent magnet (PPM) focusing structure to obtain required overall efficiency of 35%. The MPM successfully underwent stringent environmental tests and the EMI/EMC specifications as part of the qualification tests. © Anita Publications. All rights reserved.
Keywords: RF Transmitters, Microwave Power Module (MPM), Electronic Power Conditioner (EPC), Travelling wave tube (TWT), Slow-wave structure (SWS), Depressed collector, PPM focusing, Electron gun.

Peer Review Information
Method: Single- anonymous; Screened for Plagiarism? Yes
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