Parallel Coupled Microstrip Band Pass Filter

Filters are significant RF and microwave components. Lumped element filters are impractical for compact designs of wireless communications equipment, especially hand-held devices. Distributed element filter design offers a much smaller area and profile. With the advent of advanced substrate materials offering high dielectric constants with low loss, the size reduction with preserved efficiency is greatly enhanced. Transmission line filters can be easy to implement, depending on the type of transmission line used. The aim of this paper is to develop a band pass filter to use in continuous wave (CW) radio acoustic sounding system (RASS). The characteristic impedance and precise lengths are two important characteristics of transmission lines; thus those parameters are used to investigate which transmission line to use to implement filters. This paper describes about the design and fabrication of microwave band pass filter by using microstrip layout which works at 1.28 GHz. A microwave filter is a two port network used to control the frequency response within a system by allowing the transmission of certain frequencies in the passband while attenuating frequencies in the stopband. The development of the microstrip filters are simulated by using Ansoft designer SV simulator software. The final testing had done by using the vector Network Analyzer.