Using Open-Source Software QucsStudio to Design a Microwave Amplifier for SDR Applications

Abstract

This paper presents the analysis and design of a microwave amplifier for Software-Defined Radio (SDR) applications. The amplifier is implemented using the Heterojunction Bipolar Transistor technology (HBT-MMG3014NT1), designed to have the maximum transducer gain by applying distributed matching circuit elements. The amplifier is designed by using the open-source software QucsStudio (Quite Universal Circuit Simulator), with a resonance frequency design at 1.9 GHz. Then it is fabricated on a commercial FR4 substrate. The measurement results have been shown that the proposed amplifier design achieves 10.4 dB of gain at 1.9 GHz, and it has an acceptable broadband frequency response from 1.06 GHz up to 1.96 GHz with a 10 dB of attenuation. The amplifier has been tested with a primary amplitude modulation using the SDR HackRF one device.