Experimental Time-Domain Study for Bandpass Negative Group Delay Analysis With Lill-Shape Microstrip Circuit

International audienceThis paper focuses on the time-domain analysis of bandpass (BP) negative group delay (NGD) function. The innovative NGD investigation is based on the time-domain experimentation of an innovative topology of ''lill''-shape passive microstrip circuit. The design principle of the proof of concept (POC) constituted by particular microstrip shapes is described. The NGD circuit is inspired from a recent fully distributed ''li''-topology. Before the time-domain investigation, the BP NGD specifications of the circuit under study are academically defined. As practical application of the basic definition, a frequency domain validation of ''lill''-circuit is presented in the first section of the paper. The POC circuit is specified by