Abstract:The precision of the conventional terahertz transmission measurement system with a parallel-plate sample will be reduced due to the interference effect, when the frequency of the THz source drifts. To resolve the problem, a frequency-drift insensitive transmission measurement system composed of double-path is proposed. A F-P interference model is built with MATLAB. The parameters are optimized, and the effects of the terahertz source frequency drift on the precision of both the single-and double-path transmission measurement are analyzed and compared. The results demonstrated that such kind of measurement system could avoid the influence of the frequence-drift of the THz source, thus improving the measurement accuracy.
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