A 250-GHZ MICROSHIELD BANDPASS FILTER

A four-section, planar bandpass filter has been designed, fabricated a nd tested at 130-360 GHz. The filter is based on the microshield line, a half-shielded transmission line in which the conducting lines are s upported on a 1.4-mu m-thick dielectric membrane, The insertion loss o f the filter is less than 1.5 dB with a 58% relative bandwidth at 250 GHz, demonstrating the excellent performance of the microshield geomet ry. Also, a Monte Carlo routine was developed in conjuction with a sem i-empirical/semi-analytical model to allow the S-parameters of the fil ter to be derived from scalar power measurements.