Title :
Maximally Flat Negative Group-Delay Circuit: A Microwave Transversal Filter Approach
Author :
Wu, Chung-Tse Michael ; Itoh, Takayuki
Author_Institution :
Electr. Eng. Dept., Univ. of California at Los Angeles, Los Angeles, CA, USA
Abstract :
A comprehensive method to synthesize negative group delay (NGD) in the microwave regime with a maximally flat response is proposed in this paper. This method is based on transversal-filter topologies; it will be shown that by choosing proper coupling coefficients of each tap of a transversal filter, we can realize NGDs with maximally flat characteristics at the output of the transversal filter. The desired coefficients to realize maximally flat NGDs with various amount of group delay are analytically derived and tabulated in this paper. Furthermore, the results are verified experimentally through microwave transversal-filter approaches in both passive and active ways using multi-section asymmetric directional couplers and distributed amplifiers.
Keywords :
delay circuits; microwave filters; NGD; coupling coefficients; distributed amplifiers; maximally flat negative group-delay circuit; maximally flat response; microwave transversal filter approach; multisection asymmetric directional couplers; transversal-filter topology; Delays; Equations; Mathematical model; Microwave circuits; Microwave filters; Transfer functions; Anomalous dispersion; directional couplers; dispersion engineering; distributed amplifiers (DAs); negative group delay (NGD); transversal filters;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2014.2320220
