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http://dx.doi.org/10.5370/JEET.2010.5.3.497

Numerical Study on Frequency Up-conversion in USPR using MATLAB  

Roh, Young-Su (Dept. of Electrical and Electronic Engineering, Soongsil University)
Publication Information
Journal of Electrical Engineering and Technology / v.5, no.3, 2010 , pp. 497-502 More about this Journal
Abstract
In this paper, the O-mode ultrashort-pulse reflectometry (USPR) millimeter-wave signals that propagate into the plasma and cover a frequency bandwidth of 33-158 GHz are examined numerically using MATLAB. Two important processes are involved in the computation: the propagation of the USPR impulse signal through a waveguide and the frequency up-conversion using millimeter-wave mixers. These mixers are limited to intermediate frequency signals that are less than 500 mV; thus, it is necessary to disperse the impulse signal into a chirped waveform using the waveguide. The stationary phase method is utilized to derive a closed-form formula for a chirped waveform under the assumption that the USPR impulse is Gaussian. In the process of frequency up-conversion, the chirped waveform is mixed with the mixer LO signal, and the lower frequency components of the RF signal are removed using high pass filters.
Keywords
Chirped waveform; Frequency bandwidth; Frequency up-conversion; Method of stationary phase; Ultrashort-pulse reflectometry;
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Times Cited By KSCI : 1  (Citation Analysis)
Times Cited By SCOPUS : 0
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