Abstract—In this paper a novel method is presented for suppressing spurious response of parallel coupled microstrip filters. This technique is based on introducing open stubs to the filter. A third order filter is presented with central frequency at 3GHZ. The filter insertion is less than 1 dB. The harmonic suppression at the first and second harmonic is more than 20 dB and 25 dB, respectively. The performance of the new filter is also compared with characteristic of a conventionally designed filter to highlight the advantages of the proposed designed filter.
Index Terms—Bandpass filer, parallel coupled, spurious response, stub.
The authors are with the Department of Electrical Engineering of Iran University of Science and Technology, Narmak, Tehran, 16846-1311, Iran (e-mail: email@example.com, firstname.lastname@example.org).
Cite: Maryam Jaldi and Majid Tayarni, "Improvement of Stopband Property of Parallel Coupled Microstrip Bandpass Filters by Use of Open Stubs," International Journal of Information and Electronics Engineering vol. 3, no. 1, pp. 68-71, 2013.