The Butterworth microstrip hairpin filter / Hartini Mohd Isa

The purpose of this project is to design a microstrip band-pass filter operating at microwave frequencies using computer-aided design (CAD) package. A maximally flat bandpass-filter with centre frequency of 8 GHz was designed to have an insertion loss not exceeding 0.5 dB in the passband and a return loss of more than 40 dB in the stopband. To compare the performance of the hairpin filter design with its real-world counterpart, a test filter was fabricated on microstrip with a 0.5 mm substrate thickness and relative permittivity (er) of 2.33. The filter was designed, simulated and optimized with the aid of a CAD package HPEesofLibra.