Journal of the Korean Institute of Illuminating and Electrical Installation Engineers (조명전기설비학회논문지)

The Korean Institute of IIIuminating and Electrical Installation Engineers (한국조명전기설비학회)
권호 표지
DOI QR코드

DOI QR Code

Improvement of Power Spectrum in Ultrashort Pulse Reflectometry Signals Using Three Chirp Configuration

  • Roh, Young-Su (Soongsil University, Dept. of Electrical Engineering)
  • Received : 2014.01.02
  • Accepted : 2014.01.21
  • Published : 2014.03.31
Download PDF
⟨ Previous Next ⟩

Abstract

The flat power spectrum of the transmitter output signal for the desired frequency range is ideal to achieve the best performance of ultrashort pulse reflectometry. However, the power spectrum of a typical pulse generator decreases significantly as frequency increases. A configuration of three chirped waveforms was employed to improve the power spectrum of the transmitter signal at higher frequencies. To determine the amplification gain required for higher frequency components, three chirped waveforms were theoretically generated and their power spectra were measured using numerical band-pass filters. Based on the results of numerical computations, the three chirp configuration was successfully applied to the design of the transmitter for a broadband system.

Keywords

References

  1. C. Laviron, "Diagnostics for Experimental Thermonuclear Fusion Reactors," edited by P.E. Stott, Plenum Press, New York, pp.107-116. 1996.
  2. E. Mazzucato, "Microwave reflectometry for magnetically confined plasmas," Rev. Sci. Instrum., Vol. 69, No. 6, pp. 2201-2217, June 1998. https://doi.org/10.1063/1.1149121
  3. Y. Roh, C. W. Domier, and N. C. Luhmann, Jr., "Ultrashort Pulse Reflectometry for Density Profile and Fluctuation Measurements on SSPX," Rev. Sci. Instrum. Vol. 74, No. 3, pp. 1518-1521, March 2003. https://doi.org/10.1063/1.1527254
  4. S. Kubota, T. Onuma, M. Kato, A. Mase, T. Tokuzawa, N. Oyama, A. Itakura, H. Hojo, L. G. Bruskin, T. Tamano, K. Yatsu, C. W. Domier and N. C. Luhmann, Jr., "Preliminary electron density profile and fluctuation measurements on GAMMA 10 using ultrashort-pulse reflectometry," Rev. Sci. Instrum., Vol. 70, No. 1, pp. 1042-1045, Jan. 1999. https://doi.org/10.1063/1.1149498
  5. C.W. Domier, E. Chung, E. J. Doyle, H.-X. L. Liu, A. Lapidus, N. C. Luhmann, Jr., W. A. Peebles, X.-H. Qin, T. L. Rhodes, and L. Sjogren, "Development of Technology and Techniques for Reflectometry", Rev. Sci. Instrum., Vol. 63, No. 10, pp. 4666-4668, Oct. 1992. https://doi.org/10.1063/1.1143657
  6. Y. Roh, C. W. Domier, and N. C. Luhmann, Jr., "Ultrashort pulse reflectometry for electron density profile measurements on SSPX," Rev. Sci. Instrum. Vol. 72, No. 1, pp. 332-335, Jan. 2001. https://doi.org/10.1063/1.1308999
  7. Y. Roh, "Study on the Chirped Waveform of the USPR Pulse using the Impulse Response of a Waveguide", J. KIIEE, Vol. 24, No. 3, pp. 20-26, March 2010. https://doi.org/10.5207/JIEIE.2010.24.3.020
  8. Y. Roh, "Numerical Study on Frequency Up-conversion in USPR using MATLAB," J. Elec. Eng. Tech. Vol. 5, No. 3, pp. 497-502, Sept. 2010. https://doi.org/10.5370/JEET.2010.5.3.497