Bandpass filters with single transmission zeros at finite frequencies for adjusting slopes of frequency response

Author

Zaradny, Marek ; Gruszczynski, Slawomir

Author_Institution

Inst. of Telecommun. & Acoust., Wroclaw Univ. of Technol., Poland

Volume

1

fYear

2004

fDate

17-19 May 2004

Firstpage

182

Abstract

The purpose of this work is to present new possibilities of designing known microstrip band-pass filters with one or two independent transmission zeros located in the stop-band far or close to the passband. A method of independently adjusting the slopes of the filter frequency response by proper placing transmission zeros is proposed. Each zero can he tuned to reject unwanted signals in the frequency range out of the passband. The transfer function of this type of filter is analytically expressed. The behaviour of a simple third-order lossless open-loop resonator filter is presented. The experimental results obtained for a third-order filter with a fractional bandwidth of 6 % at 2.4 GHz and six-order filter with a fractional bandwidth of 7% at 1.8 GHz are in a good agreement with the theoretical ones. The excellent performance and advantages of this class of filter have been presented.

Keywords

band-pass filters; frequency response; microstrip filters; poles and zeros; resonator filters; transfer functions; 1.8 GHz; 2.4 GHz; frequency response slopes; lossless open-loop resonator filter; microstrip band-pass filters; third-order filter; transfer function; transmission zeros; Attenuation; Band pass filters; Bandwidth; Couplings; Feeds; Filtering theory; Frequency response; Passband; Resonator filters; Topology;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwaves, Radar and Wireless Communications, 2004. MIKON-2004. 15th International Conference on

Print_ISBN

83-906662-7-8

Type

conf

DOI

10.1109/MIKON.2004.1356892

Filename

1356892