An Ultra-Wideband LNA Design for 65nm CMOS Process

With the rapid development of wireless communication technology, the role of low-noise amplifiers (LNAs) in receiver systems has become increasingly important. However, conventional LNAs have limitations in terms of bandwidth, flexibility, and gain tunability, which make them difficult to meet the demands of modern high-frequency and dynamic communication systems. To overcome these challenges, this paper presents an ultra-wideband LNA design that combines a multistage filter technique and a simplified variable bias circuit, aiming to optimize the noise performance, bandwidth response, and gain control flexibility. Based on this design, simulation and experimental results show that the LNA achieves 14.5 dB, 10.2 dB, and 6.7 dB of gain in high, medium, and low gain modes, respectively. In addition, the LNA has a minimum noise figure of 2.8 dB and a high linear output power (OP1dB) of 5.7 dBm in the 8-16 GHz band. Experimental results further show that the design achieves a good balance between low power consumption, low noise and high gain, and has significant application potential for a wide range of communication systems