This paper demonstrates extremely miniaturized bandpass filters based on asymmetric coupled lines and equal reactance. By reactively loading asymmetric coupled lines while the first and the last inverters are eliminated, the proposed method overcomes the limitation of previous methods to achieve extreme miniaturization. Furthermore, the utilization of asymmetric coupled lines allows the method to miniaturize a filter with equal reactance, which provides a great advantage of low-cost fabrication. A complete set of design equations for an arbitrary number of filter order is provided for both shunt-capacitive and series-inductive loading methods. Experimental results for various miniaturized filters at 0.9 GHz are provided. An unprecedented miniaturization rate of more than 91% is demonstrated for a third-order parallel coupled-line filter.
|Number of pages||9|
|Journal||IEEE Transactions on Microwave Theory and Techniques|
|Publication status||Published - 2012 Feb|
Bibliographical noteFunding Information:
Manuscript received July 17, 2011; accepted October 14, 2011. Date of publication December 07, 2011; date of current version February 03, 2012. This work was supported by the Low Observable Technology Research Center, Agency for Defense Development and Defense Acquisition Program Administration of Korea, and by the Korea Communications Commission (KCC) under the Communications Policy Research Center (CPRC) Program supervised by the Korea Communications Agency (KCA) (KCA-2011-0902-1).
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Electrical and Electronic Engineering