A Highly Linear Wide-Band Tunable Lna for Military Radio Applications

A wide-band tunableLow-Noise Amplifier (LNA) was designed to be used in military radios. The LNAworks in the frequency range of 30–512 MHz where military walkie-talkiesoperate. To cover the wide range of operating frequencies, the output ofamplifier is divided into four sub-bands with four separate external inductorsand integrated capacitor arrays. The first part of the study analyzes theperformance parameters such as the gain, tuning, matching, noise figure, anddistortion. Layout of the design was completed, and post-layout simulations,including the layout parasitic effects, were run to quantify the performance.The LNA achieves a minimum of 12-dB gain across the entire operating frequencyrange. The minimum rejections achieved by the LNA at 10% and 20% offset fromthe center-tuned frequency were 7 dB and 13 dB, respectively. The LNA achievesa worst-case noise figure of 4.6 dB, and the impedance-match parameter (S11) isbetter than −20 dB under all the conditions. The worst cases P1dB (1-dBCompression Point) and IIP3 (3rd Order Input Intercept Point) were 9.1 dBm and18 dBm, respectively, across frequency and process–voltage–temperature corners.The design dissipates 20 mA from a 3.3-V power supply and uses a  1.5-V power supply for capacitor array termination.