Switched Low-Noise Amplifier Using Gyrator-Based Matching Network for TD-LTE/LTE-U/Mid-Band 5G and WLAN Applications

This paper presents a triple-band low-noise amplifier (LNA) fabricated using a 0.18 μm Complementary Metal-Oxide-Semiconductor (CMOS) process. The LNA uses a double-peak load network with a switched component to accomplish the triple-band operation. Moreover, noise reduction using a substrate resistor to ameliorate the noise performance is presented. Noise reduction of 1.5 dB can be achieved at 2.5 GHz without additional dc power and extra manufacturing costs. An input matching technique is realized simultaneously using a gyrator-based feedback topology. The triple-band LNA can be realized by using a dual-band input network with a switched matching mechanism. The target frequencies of the triple-band LNA are 2.3–2.7 GHz, 3.4–3.8 GHz, and 5.1–5.9 GHz, covering the operating frequency bands of time-division long-term evolution (TD-LTE), mid-band Fifth-generation (5G), LTE-unlicensed (LTE-U) band, and Wireless LAN (WLAN) technology. The measured power gains and noise figures at 2.5, 3.5, and 5.2 GHz are 12.3, 15.3, and 13.1 dB and 2.3, 2.2, and 2.6 dB, respectively.