Title :
A widely tunable RF MEMS end-coupled filter
Author :
Kraus, Garth M. ; Goldsmith, Charles L. ; Nordquist, Christopher D. ; Dyck, Christopher W. ; Finnegan, Patrick S. ; Austin, Franklin, IV ; Muyshondt, Arnoldo ; Sullivan, Charles T.
Author_Institution :
Sandia Nat. Labs., Albuquerque, NM, USA
Abstract :
A three-pole tunable end-coupled filter from 6 to 10 GHz was developed with a broad 35% tuning range. This tuning range was realized by switching distributed loading structures with radio frequency microelectromechanical systems (RF MEMS) capacitive switches. By tuning the coupling capacitors as well as the loading capacitors, the filter achieved a constant fractional bandwidth of 15±0.3% and an insertion loss ranging from 3.3 dB to 3.8 dB over the entire band. Digital switching ensured good thermal stability, and microstrip transmission lines provided lower insertion loss than with coplanar waveguide. Future improvements are expected to decrease the insertion loss to below 2.1 dB.
Keywords :
band-pass filters; coupled transmission lines; microstrip filters; microstrip lines; microswitches; microwave filters; microwave switches; 3.3 to 3.8 dB; 6 to 10 GHz; RF MEMS capacitive switches; broad tuning range; coplanar waveguide; coupling capacitor; digital switch; distributed loading structures; fractional bandwidth; insertion loss; microstrip transmission line; radio frequency microelectromechanical systems; thermal stability; three pole tunable RF MEMS end-coupled filter; Bandwidth; Capacitors; Couplings; Filters; Insertion loss; Microstrip; Radiofrequency microelectromechanical systems; Switches; Thermal stability; Tuning;
Conference_Titel :
Microwave Symposium Digest, 2004 IEEE MTT-S International
Print_ISBN :
0-7803-8331-1
DOI :
10.1109/MWSYM.2004.1336001
