A novel design of hybrid microwave bandpass filter using lumped element and microstrip line technology

The objective of this paper is to design and implement a hybrid microwave BandPass Filter (BPF) by mixing two technologies such as microstrip line and lumped element and evaluate its performance. Hybrid filter can improve the quality factor in terms of sharp cutoff frequency and minimize losses such as insertion loss, dielectric substrate loss and size of the filter can be reduced by this approach. A BPF is designed at 1800Mhz frequency. FILPRO and Advance Design System tool is used for simulation and synthesis of microstrip filter. The modern trends in wireless communication requires compact bandstop filters with good performance to supress unwanted spurious response produced by microwave circuits like mixer, power amplifier, etc. Wireless Local Area Network (WLAN) has become a standard configuration of smart mobile terminal with standards IEEE 802.11 b/g (2.4/2.45GHz) and IEEE 802.11 a (5.2/5.8GHz), which requires filters with high selectivity. To address the above mention requirement, hybrid filters with compact size and sharp cutoff frequency with minimized losses were proposed. This work is of designing and implementing hybrid filter using mixed technology of microstrip line and lumped element is designed and implemented.