Metamaterial-based Linear Phased Array Antenna with Improved Wide-Angle Scanning Bandwidth by Parasitic Metal Strips

Two metamaterial-based linear phased array antennas with improved wide-angle scanning bandwidth are designed in this study. Metamaterial antenna element consists of a metamaterial patch, periodic metal strips, distributed metal strips and slot coupling feeding structure. The bandwidth of the metamaterial antenna is improved by loading the periodic metal strips. Wide-angle scanning bandwidth of arrays is attributed to the distributed metal strips. For an E-plane array, the central element has a relative bandwidth of 30.0% (4.33-5.86 GHz) for Voltage standing wave ratio (VSWR) <2 and the main beam can scan up to +/- 70 degrees with a gain fluctuation less than 3.3 dB. For an H-plane array, the central element has a relative bandwidth of 26.2% (4.41-5.74 GHz) for VSWR <2 and the main beam can scan up to +/- 70 degrees with a gain fluctuation less than 2.5 dB. Two 7-element linear phased array antennas are fabricated to verify the scanning performance. The measured and simulation results are in good agreement. The proposed antennas can be promising candidates for C-band radar and satellite communication.