Compact Microstrip Lowpass Filter with Wide Stopband Using P-Shaped Resonator

Mohsen Hayati, Farzin Shama, Milad Ekhteraei


This paper, a compact lowpass filter (LPF) with an Elliptic function response using P-shaped resonators is presented. The LPF with simple structure results in the low insertion loss less than 0.1 dB and high return loss better than 20 dB, in the passband. The proposed filter with a -3 dB cutoff frequency of 2.61 GHz is fabricated and measured. The measured results show that the proposed LPF has significant advantages such as a wide stopband from 2.9 GHz to 17.3 GHz with the suppression level better than -20 dB, and it has an acceptable sharp frequency response in the transition band. The measurement results are in good agreement with the simulation results.


Low Pass Filter (LPF), Microstrip, P Shaped, Stopband

Full Text:



Ma, K., Yeo, K.S. and Leoe, W.M.: Ultra-wide rejection band lowpass cell, Electronics Letters. 48, 99 –100 (2012).

Hayati, M., Sheikhi, A. and Lotï¬, A.: Compact lowpass ï¬lter with wide stopband using modiï¬ed semi-elliptic and semi-circular microstrip patch resonator. Electronics letters. 46, 1507-1509 (2010).

Wei, F., Chen, L., Shi, X.W., Huang, Q.L. and Wang, X.H.: Compact lowpass ï¬lter with wide stop-band using coupled-line hairpin unit. Electronics letters. 46, 88-90 (2010).

Li, L. and Li, Z.F.: Compact quasi-elliptic lowpass ï¬lter using symmetric rectangular coupled capacitors. Electronics letters. 44, 124-125 (2008)

Sha, L., Lei, Z. and Sheng, S.: Stopband-Expanded Low-Pass Filters Using Microstrip Coupled-Line Hairpin Units. IEEE Microwave and wireless components letters. 18, 506-508 (2008).

Hong, J.S. and Lancaster, M.J.: Microstrip Filters for RF/Microwave Applications, New York John Wiley & Sons, Inc (2001).

Ma, K. and Yeo, K., S.: New Ultra-Wide Stopband Low-Pass Filter Using Transformed Radial Stubs. IEEE transaction on microwave theory and techniques. 59, 604-611 (2011)

Wang, J.P., Ge, L., Guo, Y. X. and Wu, W.: Miniaturized microstrip lowpass ï¬lter with broad stopband and sharp roll off. Electronics letters, 46, 573-575 (2010).

Hayati, M. and Shama, F.: Compact Microstrip Low-Pass Filter with wide stopband using symmetrical U-shaped resonator. IEICE Electronics Express 9.3, 127-132 (2012).

Hayati, M., & Yousefzadeh, Y.: Compact Lowpass Filter with Wide Stopband Using Windmill-Shaped Resonator. Arabian Journal for Science and Engineering, 39(4), 3033-3038 (2014)

Raphika, P. M., P. Abdulla, and P. M. Jasmine. : Compact lowpass filter with a sharp roll-off using patch resonators. Microwave and Optical Technology Letters 56.11, 2534-2536 (2014).

Faraghi, Ahmad, Mohammad Ojaroudi, and Noradin Ghadimi. : Compact microstrip low-pass filter with sharp selection characteristics using triple novel defected structures for UWB applications. Microwave and Optical Technology Letters 56.4, 1007-1010 (2014).

Chen, Xianhong, et al.: Compact lowpass filter with wide stopband bandwidth. Microwave and Optical Technology Letters 57.2, 367-371 (2015).



  • There are currently no refbacks.

© Copyright 2007-2016 JMOe Brazilian Microwave and Optoelectronics Society (SBMO) and Brazilian Society of Electromagnetism (SBMag)