International Journal of Electrical and Computer Engineering (IJECE) Vol. 10, No. 5, October 2020, pp. 5400~5408 ISSN: 2088-8708, DOI: 10.11591/ijece.v10i5.pp5400-5408  5400 Journal homepage: http://ijece.iaescore.com/index.php/IJECE Design of L-S band broadband power amplifier using microstip lines Mohamed Ribate 1 , Rachid Mandry 2 , Jamal Zbitou 3 , Larbi El Abdellaoui 4 , Ahmed Errkik 5 , Mohamed Latrach 6 , Ahmed Lakhssassi 7 1,2,3,4,5 Mechanical, Energy, Electronics and Telecommunication Laboratory (LMTEE), Faculty of Sciences and Techniques, Hassan 1st University, Morocco 6 Microwave Group ESEO Angers, France 7 Quebec University, Canada Article Info ABSTRACT Article history: Received Nov 26, 2019 Revised Apr 21, 2020 Accepted May 4, 2020 This contribution introduces a novel broadband power amplifier (BPA) design, operating in the frequency band ranging from 1.5 GHz to 3 GHz which cover the mainstream applications running in L and S bands. Both matching and biasing networks are synthesized by using microstrip transmission lines. In order to provide a wide bandwidth, two broadband matching techniques are deployed for this purpose, the first technique is an approximate transformation of a previously designed lumped elements matching networks into microstrip matching circuits, and the second technique is a binomial multi-sections quarter wave impedance transformer. The proposed work is based on ATF-13786 active device. The simulation results depict a maximum power gain of 16.40 dB with an excellent input and output matching across 1.5 GHz ~ 3 GHz. At 2.2 GHz, the introduced BPA achieves a saturated output power of 16.26 dBm with a PAE of 21.74%, and a 1-dB compression point of 4.5 dBm input power level. The whole circuitry is unconditionally stable over the overall bandwidth. By considering the broadband matching, the proposed design compares positively with the most recently published BPA. Keywords: Broadband biasing Broadband matching L and S bands Microstrip Power amplifier Copyright © 2020 Institute of Advanced Engineering and Science. All rights reserved. Corresponding Author: Mohamed Ribate, Mechanical, Energy, Electronics and Telecommunication Laboratory (LMEET), Faculty of Sciences and Techniques, Hassan 1st University, University Complex, Casablanca Road, Km 3.5, B.O Box 577, Settat, Morocco. Email: ribate.mohamed@gmail.com 1. INTRODUCTION In today’s communication age, the world as we know would be unimaginable without the RF and microwave technology [1]. Nowadays, where telecommunication has turn into a standard, practically, every wireless device has some kind of transceiver, and inherently a power amplifier (PA) permitting it to connect to the mobile cellular networks, Wi-Fi networks, or in a broad sense, to the available wireless networks [2-4]. Basically, PA applications spend a wide range of fields including the traditionally telecommunication, sensing, spectroscopy, navigation, detection of foreign bodies, heating, diagnostics, imaging and treatment applications, and the current trend toward to the Internet of Thing represent just a few examples [5-8]. On the other hand, the cellular mobile communication has reached tremendous advances in terms of technology and innovation as well as commercial accomplishment [9]. However, with the explosive proliferation of the RF and wireless communication standards, driven mostly by the growing demands to transmit an increasing amount of data, besides the growing need of rapid transport of signals in the next generation communication systems as well as the wider signal channels requirement, will lead in a deeply interest in broadband power amplifiers (BPAs) [10-14]. Such devices can supersede multi narrowband and