A 6.8 - 9.4 GHz LNA Achieving 36.5 dB Peak Gain, Consuming 4.28 mW with an Adjustable Threshold Limiter for IR-UWB Applications

This paper presents a low-power staggered tunning LNA with a variable threshold limiter designed for impulse-radio ultra-wideband (IR-UWB). This amplifier has a high gain of 36.5 dB with a 3dB
$S_{21}$
frequency of 6.8 - 9.4 GHz while consuming 4.28 mW from a 0.8 V supply. The input return loss is better than 8 dB across the band and 10 dB from 6.9 GHz. The output return loss is better than 18 dB across the operating bandwidth. At 9 GHz, the minimum noise figure measured is 4.85 dB. The OP1dB compression point is measured at 7.8 GHz as -5.5 dBm. We also present an adjustable threshold limiter, providing additional protection over a typical diode limiter circuit. This amplifier is fabricated in a 45nm PD-SOI process. To the author's knowledge, this LNA demonstrates the highest linear figure of merit (FoM) in C and X band work.