A broadband receiver front-end with low noise figure and flat conversion gain response is presented in this paper. The receiver front-end is a part of the broadband spectrum sensing receiver and processes 30-40 GHz of broad input spectrum followed by down-conversion to DC-10 GHz of IF signal. The proposed work is comprised of a low noise amplifier (LNA), on-chip passive Balun, down conversion mixer, and output buffer. To achieve front-end target specification over 10 GHz input bandwidth, the stagger-tuned LNA is employed and the down conversion mixer is loaded with a 3rd-order LC ladder low pass filter. The prototype chip was implemented in 45 nm CMOS technology. The chip achieves 10.3-16.5 dB conversion gain, 5.9 dB integrated NF, and -11 dBm IIP3 from 30 to 40 GHz. The chip is realized within 0.42 mmand consumes 96 mW from a 1.2 V supply.