A miniaturized interdigital hairpin microstrip bandpass filter design

Abstract

Modern communication technology is advancing every day. It is becoming more efficient and miniaturized. The efficiency of the communication technology depends upon the performance of the filter used in the system. That’s why extensive research is going on to improve the filter performance as well as to reduce its size. In this thesis we have proposed a four-pole elliptic function band-pass filter designed using compact miniaturized microstrip interdigital hairpin resonator. Miniaturization hairpin resonator is realized by using an interdigital structure having parallel coupled lines. Many works are going on in the field of filter designing. The most recent works has been studied in this thesis to obtain the most suitable design for specific application. We have used the full-wave simulator IE3D to design the interdigital hairpin resonator. We choose RO4003C substrate for our design as it has many advantages in high frequency applications. Finally a filter with chip area of 28.2 * 20.2 mm2 and center frequency at 2.4GHz with a 3db bandwidth of 220 MHz has been proposed. Its upper cutoff and lower cutoff frequencies are respectively 2.53 GHz and 2.31 GHz.