EMI Design Prediction and Test Results on VHF Transponder

Abstract

This paper discusses various aspects of EMI design, prediction and EMI test results obtained on the VHF transponder system, which is a primary unit for predicting the SEO-II satellite range which would be used for updating the satellite orbital parameters. The basic concept of VHF transponder is to employ a method of measuring the range by transmitting the continuous modulated waves and measuring the propagation delay of the transponded signal from the satellite. The range information obtained from the transponded signal is very much valuable and hence it is necessary to ensure that the VHF transponder operates satisfactorily in the satellite environment against EMI. Hence the EMI considerations like design, prediction and test on VHF Transponder are carried out and found to be useful against EMI. The comparison between the EMI prediction and the EMI test observation results is also given.

Indexing Terms:

• EMI Design
• Prediction
• Compatibility Tests

Additional information

Notes on contributors

Rajappa

Rajappa: Obtained B.E. (Electronics) from Bangalore University in the year 1975. In July 1975 he joined R.V. College of Engineering, Bangalore as a Lecturer in Electronics and taught the undergraduate courses. In June 1976, he joined ISRO Satellite Centre, Department of Spaces, Bangalore, as an Engineer in the Quality Assurance and Test and Evaluation Group. He is actively engaged in the test and evaluation of Spacecraft communication systems and related EMI/EMC activities. Currently he is working on computer aided evaluation of Satellite communication systems.

S.N. Prasad

Prasad, S N: After obtaining M. Tech degree from the Institute of Radio Physics & Electronics, Calcutta University, he joined Central Electronics Engineering Research Institute (CEERI), Pilani in 1969. In CEERI he worked on the development of integrated circuit TV and other VHF communication systems.

In 1972 he joined the Electronic Division of ISRO Satellite Centre, Bangalore. He has worked on various ground tracking systems for ARYABHATA satellite. He has designed and developed the VHF Tracking Transponder and UHF Transponder for transponding meteorological data from unattended platforms. Currently he is engaged in designing and developing a VHF Tracking Transponder for the next satellite, the satellite for Earth observation (SEO-II). He is also involved in TTC system planning for another satellite, the Indian Remote Sensing Satellite (IRS).