A Two-stages Microstrip Power Amplifier for WiMAX Applications

Abstract

Amplification is one of the most basic and prevalent microwave analog circuit functions. Wherefore power amplifiers are the most important parts of electronic circuits. This is why the designing of power amplifiers is crucial in analog circuit designing. The intent of this work is to present an analysis and design of a microwave broadband power amplifier by using two stages topology. A two stages power amplifier using a distributed matching network for WiMAX applications is based on ATF-21170 (GaAs FET). The configuration aims to achieve high power gain amplifier with low return loss over a broad bandwidth. The proposed BPA is designed with a planar structure on an epoxy (FR4) substrate. The planar structure is also utilized for getting the good matching condition. The advanced design system (ADS) software is used for design, simulation, and optimization the proposed amplifier. The complete amplifier achieves an excellent power gain; is changed between 28.5 and 20 dB with an output power of 12.45dBm at 1dB compression point. For the input reflection coefficient ( S11) is varied between -20 and -42 dB. While the output reflection coefficient (S22) is varied between -10 dB and -49 dB over the wide frequency band of 3.2-3.8 GHz.

Analysis and design of the biasing network for 1 GHz bandwidth RF power amplifier

“…As a result, the QWML is not perfectly open at the RF signal at the biasing tee. To overcome this problem, the biasing network is designed using the QWML and the radial stub at the end of the QWML [5], [7], [16]. The radial stub will create short circuit at the connected point.…”

Wideband power amplifier based on Wilkinson power divider for s-band satellite communications

“…The design provides up to 12.4dB gain, but it suffers from limited bandwidth where covers from 5.6GHz to 6GHz (0.4GHz). Recently, many researchers have designed and developed power amplifiers, but most of the designed power amplifiers have been suffered from limited bandwidth, and high inter-modulation distortion which is considered a measure of linearity of the amplifier [14][15][16][17][18][19][20][21][22][23][24][25]. In [14], authors designed single stage wideband power amplifier with flat gain of 10-11.8 dB, and good input and output return loss.…”

“…In [21], high efficiency power amplifier based on AlGaN/GaN-HEMT technology is presented. The proposed design achieves efficiency of 34 % with high output power of 30 W. In [22], two stages power amplifier has been designed based on distributed matching network in order to obtain good impedance matching and high gain. Although the designed amplifier achieves an excellent gain of 20-28 dB.…”