Wide-Angle Scanning Phased Array With Pattern Reconfigurable Elements

A novel phased array is presented to extend array scanning range by using pattern reconfigurable antenna elements and weighted thinned synthesis technology in this paper. The pattern reconfigurable microstrip Yagi antenna element is used as a basic element in array and it is capable of reconfiguring its patterns from broadside to quasi-endfire radiation by shifting states of the PIN diode switches integrated on parasitic strips. A weighted thinned linear array synthesis technique is analyzed and some interesting conclusions have been made. A linear array composed of eight pattern reconfigurable antenna elements is manufactured to demonstrate the excellent performance of the array. The active element pattern of each element is measured and pre-stored. Based on active element patterns and weighted thinned linear array synthesis technique, the pattern scanning performance of the novel array is synthesized. The results indicate that the array can scan its main beam from phi = -60 degrees to phi = 60 degrees in H-plane with gain fluctuation less than 3 dB while maintaining low side lobes, and the 3 dB beam width coverage is about from phi = 68 degrees to phi = 68 degrees. The performance is superior to the traditional phased array made of wide-beam elements.