THz Spectrum Analyzer

ABSTRACT: The emergence of a diverse selection of new high-power terahertz sources has highlighted the critical need for a calibrated, independent, broadband terahertz spectrum analyzer. Present spectrum analyzers work at either microwave frequencies or in the far infrared, and only source specific detection mechanisms are available, limiting broad comparison and classification. The characterization of high power sources is essential as the health impact (if any) of such devices is investigated, and the classification of these devices based on power frequency distribution by an independent and common spectrum analyzer is essential for side-by-side comparison. We propose to implement a true THz spectrum analyzer using a rapidly scanning circular involute delay line coupled with a high speed broadband pyroelectric detector in a modified Michelson interferometer configuration. During phase I, we demonstrated the feasibility of this approach coupled with both pulsed and CW THz sources. In phase II, we will realize a compact (12"x8"x5"), real-time (>5 Hz), broadband (>10THz), high resolution (<10GHz) THz spectrum analyzer. Development will include several field tests at high power THz sources of interest to the Air Force, and a calibration process will be established to insure robust source classification, regardless of emission mechanism or output power. BENEFIT: The resulting THz spectrum analyzer will be a useful diagnostic tool for new THz sources and as a calibration tool for existing sources. We anticipate as commercial applications become available for THz systems, this will be an essential tool for the calibration, lifecycle measurement and maintenance of THz sources and systems.