Gain-flatness considerations on the ultra-wideband low-noise amplifier design

Conventional ultra-wideband low-noise amplifiers require a flat gain over the entire 7.5-GHz bandwidth, which severely restricts the trade-off space for noise and power requirements. This paper proposes a relaxed gain-flatness requirement based on system level investigations. Considering the wireless transceiver front-end with propagation channel characteristics, the unflat-gain low-noise amplifier with an incremental gain characteristic does not degrade the performance of overall system. As an alternative to its flat-gain counterpart, the proposed unflat gain requirement greatly eases the design challenges to low-noise amplifier for ultra-wideband wireless receivers.