Research
Swipe to view
Title : | Design and Modeling of a Futuristic High-Efficiency High-Frequency Vacuum RF Amplifier for Space Satellite Communication |
Area of research : | Engineering Sciences |
Focus area : | RF Technology, Satellite Communication |
Principal Investigator : | Dr. Amitavo Roychoudhury, CSIR- Central Electronics Engineering Research Institute, Rajasthan |
Timeline Start Year : | 2024 |
Timeline End Year : | 2027 |
Contact info : | amitavorc2[at]gmail[dot]com |
Details
Swipe to view
Executive Summary : | A Space TWT which is a very high order vacuum microwave device can be used as a RF amplifier in many satellite communication systems to handle a large number of downlink signals. M/s Hughes, USA and M/s Thales, Germany are the only suppliers of space TWTs in the world. It’s not easy to get space TWTs due to their strategic importance. Stringent requirements of Space TWTs include high efficiency, high linearity and reliability, long life etc. along with wide bandwidth, high gain at required output power and frequency band. The challenge for the space TWT designer is to design TWT with high gain so that it can be operated close to the saturation value. To achieve high gain it is require to evaluate overall TWT performance using computer simulation approach. In the proposed design and modeling work, different components of high frequency, high efficiency space TWT will be designed and simulated. Complete TWT will also be simulated using CST to evaluate the complete RF performance. TWT mainly consists of electron gun, helical slow wave structure, focusing system (PPM), depressed collector and I/P as well as O/P couplers. In-house developed software packages along with commercially available software will be used for the design of different components of a helix TWT. Electron gun for space TWTs can be designed using M-type dispenser cathode having current density value of ~1Amp/cm² in order to have long life and reliability. Efforts will be made to achieve laminar electron beam with beam ripples less than 10% at required operating voltages and beam current for the designed PPM focusing field. The helix SWS which supports the propagation of the RF signal and controls the beam-wave interaction will be optimized for better stability of the device. Dimensions of helix and APBN support rods will be optimized for achieving the highest possible interaction impedance of the helix SWS. The performance of the TWT will be simulated using SUNRAY-1D and 2.5D codes and CST for large signal analysis of the helix TWT. HFSS and CST codes are used for the design of couplers with helix SWS to achieve return loss better than ~-15dB over the desired band. MDC will be designed to recover maximum possible kinetic energy of the spent electron beam at different stages of the collector. Due considerations will be given to thermal and structural aspects in designing the different components of the TWTs. ANSYS software will be used for detailed thermal and structural analysis of different assemblies of a space TWT. The proposed work will lead to successfully achieve the state of art performance of a high frequency, high efficiency space TWT that will be the future requirement for ISRO’s space satellite communication systems. Once the capability is build up, the space TWT of different specifications can be produced indigenously as per the needs of the user(s). Moreover it is a step towards Atmanirbhar Bharat and will help India to become self-sufficient in space sector. |
Co-PI: | Dr. Sanjay Kumar Ghosh, CSIR- Central Electronics Engineering Research Institute, Pilani, Rajasthan-333031 |
Total Budget (INR): | 30,60,603 |
Organizations involved
Swipe to view
Implementing Agency : | Csir- Central Electronics Engineering Research Institute, Rajasthan |
Funding Agency : | Anusandhan National Research Foundation (ANRF)/Science and Engineering Research Board (SERB) |
Source : | Anusandhan National Research Foundation/Science and Engineering Research Board (SERB), DST 2023-24 |