Title :
Ultra wide stop band LPF with using defected microstrip structures
Author :
Mallahzadeh, Ali Reza ; Rahmati, Bahman ; Alamolhoda, M. ; Sharifzadeh, R. ; Ghasemi, A.H.
Author_Institution :
Electr. & Electron. Eng. Dept., Shahed Univ., Tehran, Iran
Abstract :
A novel harmonic-suppressed microstrip stepped impedance lowpass filter (LPF) using Defected Microstrip Structure (DMS) is proposed. In order to cause the spurious passband suppression, appropriate geometries of DMS resonators have etched in the low impedance sections. Due to the attenuation poles of two kinds of resonators, it is found that harmonic responses are not only suppressed effectively, but a wide stopband can be also obtained. A demonstration filter with cutoff frequency at 2.5 GHz has been designed, fabricated and measured. The proposed filter also exhibits a very wide stopband of 145% (referred to a suppression degree of 20 dB).
Keywords :
band-stop filters; defected ground structures; electric impedance; harmonics suppression; low-pass filters; microstrip resonators; microwave filters; ultra wideband antennas; DMS resonator; attenuation pole; defected microstrip structure; frequency 2.5 GHz; harmonic suppression; lowpass filter; microstrip stepped impedance LPF; passband suppression; ultra wide stop band filter; Filtering theory; Impedance; Low pass filters; Microstrip; Microstrip filters; Microwave filters; Resonator filters; Defected Microstrip Structure (DMS); harmonics suppression; stepped impedance lowpass filters;
Conference_Titel :
Antennas and Propagation (EUCAP), 2012 6th European Conference on
Conference_Location :
Prague
Print_ISBN :
978-1-4577-0918-0
Electronic_ISBN :
978-1-4577-0919-7
DOI :
10.1109/EuCAP.2012.6206280
