Dual-Band Power Amplifier Design at 28/38 GHz for 5G New Radio Applications

This paper presents the design of a dual-band power amplifier (PA) featuring similar performance at 28 GHz and 38 GHz. In the new radio (NR) of the fifth generation (5G) communication system, the inter-band carrier aggregation technique is commonly adopted for data rate enhancement. In such configuration, operation at both bands of the 5G frequency range 2 (FR2) spectrum is often necessary. The stacked-FET topology was adopted for mitigation of the gain roll-off with frequency to achieve similar performance at both frequency bands. Implemented in the commercial 0.15-μm gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) technology, the PA delivered a small signal gain of 18.5/18 dB, an output power at saturation (Psat) of 28.5/28.2 dBm, and a peak power-added efficiency (PAE) of 39%/36% at 28/38 GHz, respectively. The measurement results have demonstrated great potential of the proposed PA for 5G NR applications.