This paper represents a digitally controlled, gain programmable SiGe BiCMOS low noise amplifier operating at 1-1.8 GHz used in multi-band navigation receiver front-end. An inductively degenerated common emitter LNA with an off-chip second order band-pass filter is adopted to achieve wideband input impedance matching without degrading much noise performance. The current splitting technique is used which doesn't affect the input impedance matching and the gain flatness of the LNA when gain varies. The simulation results show a 23.5 dB maximum gain with noise figure of 1.9 dB and IIP3 of 0 dBm. The LNA can be tuned from 3.5 dB to 23.5 dB, only drawing 3.8 mA current from 3.3 V power supply.