This work presents an ultra-wideband receiver front-end, designed for a reconfigurable frequency modulated continuous wave (FMCW) radar. A variety of innovative circuit components and design techniques were employed to achieve the ultra-wide bandwidth, low noise figure, good linearity and circuit ruggedness to high input power levels. The designed front-end is capable of achieving 1.5-40 GHz bandwidth, 30 dB conversion gain, a double sideband noise figure of 6-10.7 dB, input return loss better than 7.5 dB and an input referred 1 dB compression point of-23 dBm. The front-end withstands continuous wave power levels of at least 25 dBm and 20 dBm at low band and high band inputs respectively. The DC power is supplied from a 3 V power source and the consumption is 302 mW when the low band is active and 352 mW for the high band case.