Picosecond-domain radiation pattern measurement using fiber-coupledphotoconductive antenna

摘要

The photoconductive terahertz measurement technique was used fornmeasurement of the radiation pattern from thick metal slits. Picosecondnpulses were generated and detected by an ultrafast optoelectronicntechnique using a femtosecond pulse laser and a subpicosecondnphotoconductor. Photoconductive sampling measurements of thenpolarization-dependent diffraction of the picosecond electromagneticnpulses showed the highly polarized radiation characteristics of thenphotoconductive probing antenna (PCPA) compared with thenfinite-difference time-domain simulation. The radiation patterns fromnthe slits were measured using a fiber-coupled PCPA. Investigation of thenspatiotemporal radiation pattern from a thick metal slit shows thenusefulness of the measurement set-up for time-domain and broadbandnantenna characterization. Together with the time-domain radiationnpattern, the frequency-domain radiation pattern from the experimentalntransient response is presented in both amplitude and phase. It isndemonstrated that the time-domain radiation pattern measurement usingnthe photoconductive terahertz radiation technique is a promisingncharacterization method for millimeter-wave and submillimeter-wavenantenna time-domain testing