Browse > Article
http://dx.doi.org/10.12673/jant.2011.15.5.789

Linear Characteristics Improvement of X-band TWT Amplifier for Satellite Communication with Linearizer  

Choi, Won (Department of Electronics Engineering, University of Incheon)
Yang, Hong-Sun (Victek. Co., Ltd.)
Koo, Kyung-Heon (Department of Electronics Engineering, University of Incheon)
Publication Information
Journal of Advanced Navigation Technology / v.15, no.5, 2011 , pp. 789-794 More about this Journal
Abstract
This paper has analyzed the AM-AM and AM-PM characteristics of 7.9 GHz~8.4 GHz X-band TWT used for satellite communication and improved its linearity and IMD performance by using linearizer. The TWT amplifier with the linearizer shows better AM-AM and AM-PM conversion, and has increased 1 dB compression point by 12.3 dB and $2.0^{\circ}/dB$ phase distortion point by 10 dB. The 3rd order intermodulation distortion, IMD3 is measured to be 37.0 dBc that is 16.2 dB improvement at the operating output. This paper also proposed the measurement method of IMD for high power amplifier, and that TWT amplifier can have better linearity and output power by compensating for the AM-PM characteristics.
Keywords
TWT; Predistorter; SSPA; AM-AM; AM-PM; Intermodulation;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Jan M. Weekley, Bill J. Mangus, "TWTA versus SSPA: A comparison of on-orbit reliability data," IEEE Trans. on Electron Devices, vol.52, no.5, pp.650-652, May 2005.   DOI   ScienceOn
2 Allen Katz, "TWTA linearization," The Microwave Journal, vol. 39, no.4, pp.78-90, April 1996.
3 Steve C. Cripps, RF power amplifier for wireless communication, Artech House, 2006.
4 Xin Hu, Gang Wang, Zi-Chen Wang, and Ji-Run Luo, "Predistortion linearization of an X-band TWTA for communications applications," IEEE Trans. on Electron Devices, vol. 58, no.6, pp. 1768- 1774, June 2011.
5 K. Kanto, A Satomi, Y. Asahi, Y. Kashiwabra, Y. Matsushita, K. Takagi, "An X-band 250W solid-state power amplifier using GaN power HEMTs," IEEE Radio and Wireless Symposium, pp.77-80 Jan. 2008.
6 Ji Han Joo, Min Ho Son, Yong Dug Lee, Jin Joo Choi, "Feedfoward and predistortion linearizers on an X-band helix TWT," IEEE International Vacuum Electronics Conference, pp. 174-175, April 2004.