—This paper proposes a microstrip diplexer using folded single stepped-impedance resonator for 3G microcell stations. The filters are designed based second-order with side coupled excitation. The measured uplink band is at 1900-1965 MHz having a passband attenuation of 1.94 dB and return loss of 19.5 dB, while downlink band is at 2085-2135 MHz having a passband attenuation of 2.20 dB and return loss of 22.3 dB, where isolation between uplink and downlink band is 18.4 dB. In addition, second harmonic is suppressed at greater than 40 dB upto 4700 MHz. The advantages of our diplexer include low profile, compactness, high isolation, and high selectivity.
—Microstrip, diplexer, stepped-impedance resonator, SIR.
S. Theerawisitpong and P. Pinpratomrat are with the Department of Industrial Education, Faculty of Technical Education, Rajamangala University of Technology Thanyaburi, Pathum Thani, Thailand (e-mail: firstname.lastname@example.org, email@example.com).
Cite:S. Theerawisitpong and P. Pinpathomrat, "A Microstrip Diplexer Using Folded Single Stepped-Impedance Resonator for 3G Microcell Stations," International Journal of Information and Electronics Engineering vol. 6, no. 3, pp. 171-174, 2016.