In this paper, we propose an electrically tilting system based on a null-steering in order to solve the problem of the shadowing loss caused by the mechanically tilted antenna system in mobile services. Especially, we improve the downward shadowing loss by eliminating or moving the vertical beampattern nulls between $-30^{circ}{sim}0^{circ}$ to be able to tilt the downward beampattern between $-10^{circ}{sim}0^{circ}$. The antenna has 14.5 dBi gain and side lobe level (SLL) is lower than -18 dB within downward tilting range. The isolation of polarization is greater than 30 dB when running in electric tilt down to $-10^{circ}$. To verify this paper, we made the base-station antenna for W-CDMA and beam tilting devices, and verified the performances.