Phased arrays have been required to operate over wide bandwidths and wide scan angle to support multifunction operation in both telecommunication and radar. In response to that need, this study firstly analyses the performance of the connected planar tapered slot antenna array and finds that the mutual coupling is essential and has good effect in wideband antenna array design. Then the authors design a wideband widescan planar tapered slot antenna array system with novel dual-parabola tapered slot antenna elements and feed network. This array can operate from 1.6 to 9 GHz and scan angle up to 45°. Both simulation and measurement results are shown to certificate the performance of the proposed antenna array.