volume | PIER Journals

Abstract

This paper presents the design and implementation of a C-Band Frequency Generator developed for Space-borne Synthetic Aperture Radar. This Frequency Generator subsystem generates stable and coherent reference signals for all the sub-systems of C-Band Synthetic Aperture Radar payload. Frequency Generator based on frequency multiplication technique generates various coherent signals namely 500 MHz signal for digital clock, local oscillator (LO) signals of 900 MHz and 4500 MHz needed for receivers and chirp signal of 5400±37.5 MHz. This chirp signal is generated by direct modulation of the full bandwidth baseband signal of DC-37.5 MHz at 4500 MHz and subsequently mixing with 900 MHz signal. Frequency generator unit is realized in a compact two-tier architecture, using novel concept of full chirp modulation, resulting in 6° rmsphase error in the transmit chirp signal along with in-band spurious rejection better than 20 dBc, whereas other coherent frequencies resulting in out of band spurious rejection better than 53 dBc against the specification of 40 dBc.

1. Moreira, A. and G. Krieger, "Spaceborne synthetic aperture radar (SAR) systems: State of art and future developments," 33rd European Microwave Conference Proceedings (IEEE Cat. No.03EX723C), IEEE, Munich, Germany, 2003.

2. Misra, T., S. S. Rana, N. M. Desai, et al. "Synthetic aperture radar payload on-board RISAT-1: Configuration, technology and performance," Current Science Journal, 2013.

3. Rao, Ch. V. N., B. V. Bakori, J. Dhar, et al. "RF and microwave subsystems for RISAT-1 SAR payload," Signatures, Newsletter of the ISRS-AC, Vol. 24, No. 2, Apr. 2012.

4. Mishra, C., A. V. Garcia, E. S. Sinencio, et al. "A carrier frequency generator for multi-band UWB radios," IEEE Radio Frequency Integrated Circuits (RFIC) Symposium, 2006, IEEE, San Francisco, CA, USA, 2006.

5. Huang, X., W. Deng, H. Jia, et al. "A C-band FMCW radar transmitter with a 22 dBm output power series-stacking CMCD PA for long-distance detection in 180-nm CMOS technology," IEEE International Conference on Integrated Circuits, Technologies and Applications (ICTA), IEEE, Zhuhai, China, 2021.

6. Madiwalesh, M. P., M. S. Ruchit, M. V. Harikrishna, et al. "Design and development of agile C-band synthesizer for RADAR," 2018 IEEE MTT-S International Microwave and RF Conference (IMaRC), IEEE, Kolkata, India, 2018.

7. Ansoft High frequency Structure Simulator User's Manual, Version 17.

8. Dhar, J., "Enclosure effect on microwave power amplifier," Progress In Electromagnetics Research C, Vol. 19, 163-177, 2011.
doi:10.2528/PIERC10112604

9. Dhar, J., S. K. Garg, R. K. Arora, B. V. Bakori, and S. S. Rana, "C-band pulsed solid state power amplifier for spaceborne applications," Progress In Electromagnetics Research Letters, Vol. 23, 75-87, 2011.
doi:10.2528/PIERL11020907

10. Bin Muhammad Nor, M. Z., S. K. Abdul Rahim, M. I. bin Sabran, and M. S. bin Abdul Rani, "Wideband planar Wilkinson power divider using double-sided parallel-strip line technique," Progress In Electromagnetics Research C, Vol. 36, 181-193, 2013.

11. Srivastava, S., G. V. Reddy, J. Dhar, et al. "Active frequency doubler at X-band," 2022 IEEE Microwaves, Antennas, and Propagation Conference (MAPCON), IEEE, Bangalore, India, 2022.

12. Camargo, E., Design of FET Frequency Multipliers and Harmonic Oscillators, Artech House, 1998.

13. Klymyshyn, D. M. and Z. Ma, "Active frequency-multiplier design using CAD," IEEE Transactions on Microwave Theory and Techniques, Vol. 51, No. 4, Apr. 2003.
doi:10.1109/TMTT.2003.809183

14. Zhou, M., S. Tang, W. Wang, et al. "A frequency multiplication method based on extracting harmonic from narrowpulse," IEEE Access, Jul. 2019.

15. Mishra, S., N. Singh, J. Dhar, et al. "A GaAs based miniaturized C-band double balanced resistive IQ modulator for synthetic aperture radar (SAR) applications," IEEE Recent Advances in Geoscience and Remote Sensing: Technologies, Standards and Applications (TENGARSS), 2019.

16. Agrawal, G., P. Sinha, J. Dhar, et al. "Design and development of broadband and compact size IQ demodulator at 850 +- 112.5 MHz," 6th International Conference for Convergence in Technology (I2CT), Apr. 2-4, 2021.

17. Scott, A. W., Cooling of Electronic Equipment, John Wiley & Sons, 1974.

Dr. Nidhi Singh

Dr. Jolly Dhar

Dr. Cheemalamarri Venkata Narasimha Rao

Dr. Gurleen Singh Rajpal