The limiting low noise amplifier (Limiting LNA) is an integrated RF chip designed for radar and communication receiver front-ends, integrating a limiting protection circuit and a low noise amplifier into a single component. The front-end limiter suppresses high-power interference, transmit leakage signals and pulse spikes, preventing high-power signals from damaging subsequent amplifier transistors. The rear low-noise amplifier amplifies weak echo or tiny RF signals while maintaining an ultra-low noise figure to guarantee system receiving sensitivity.
Conventional discrete designs with separate limiter and standalone LNA occupy more array space and introduce extra two-stage insertion loss. The all-in-one limiting LNA shortens signal paths, reduces loss, shrinks PCB footprint and optimizes system SWaP performance.
It is widely adopted in Ku-band phased array T/R receive channels, satellite communication receivers, vehicle detection radars and electronic reconnaissance equipment. Key parameters include noise figure, small-signal gain, limiting threshold, insertion loss and VSWR.