Abstract: A shunt feedback inductorless UWB LNA implemented in a 180 nm CMOS technology is here reported. Covering a 3 to 5 GHz band,the circuit uses resistive current reuse technique as self bias to obtain the relative gain within wide band,and the noise cancellation technique to cancel part of thermo noise in the channel,which can effectively lower NF over the desired UWB band.The simulation results showed that the designed LNA achieves a NF of 4.6 dB in the 3~5 GHz UWB band and a power gain of 11~13.9 dB.The active inductance design greatly reduces the chip size,which has great potential in commercial applications.