A broadband planar antenna with stable radiation patterns is presented. It consists of a suspended radiator fed by a vertical feed through an n-shaped microstrip. The measured impedance bandwidth is 3.1-5.1 GHz for a return loss of |S11| < -10 dB, and an average gain of 7.7 dBi is achieved. There is no beam squinting across the operating frequency band. Also, this cost effective design has a high manufacturability and good mechanical tolerance.