A Novel Broadband Microstrip Array Antenna with Beam Tilt

The array antenna is fed by a six-way stripline network, which consists of a equal Wilkinson power divider(PD) and four unequal PDs. The coupling between the patch elements and the feed network is realized by using metalized via. A 6×6 array antenna has been fabricated and measured. The measured results are in good agreement with the simulated values, which show that the proposed antenna has a impedance bandwidth of about 12.89% for |S11|<-10dB. The sidelobe levels (SLL) in E-plane and H-plane of the antenna are less than -12dB and -15dB, respectively. Moreover, stable radiation patterns with beam tilt of 40°and a peak gain of 13.21–16.82dBi are achieved within the operating band. The proposed antenna has a broad bandwidth, low back-radiation level, and low fabrication cost.