Design of Ka-Band Power Amplifier and Low-Noise Amplifier for 5G Communication Systems

The primary challenge in designing the front-end of any communication system is the amplifiers. These amplifiers, although linear structures, rely on nonlinear devices for their designing. The amplifier should balance performance and complexity, especially for 5G applications. These power amplifiers (PAs) for transmission and low-noise amplifiers (LNAs) for reception demand low latency, high speed, increased bandwidth, accommodation of more users per channel/systems, higher power outputs, and support for MIMO applications. Moreover, with allotted spectrum allocation for global 5G operations, both sub-6 GHz and Ka-band frequencies are to be utilized, with higher challenges in Ka band (24.25–32 GHz). These challenges are met with proper device selection, optimum matching, and efficient MMIC design. In this work, we aim to design a PA and LNA on Gallium Nitride High-Electron-Mobility Transistor (GaN HEMT) device using low-pass filter-type impedance transformer in order to meet these challenges. The designed amplifiers are targeted to operate around 28 GHz with 400 MHz of bandwidth (minimum). The designed PAs are able to provide 25% and 80% PAE for single-stage and dual-stage Pas, respectively. Both the designs are more than 25 dBm output power amplifiers. The single-stage LNA is providing 6 dB gain and 2.2–3.3 dB noise figure, whereas for the three-stage LNA design, gain achieved is 10 dB gain and 5 dB noise figure in desired frequency range.