Wideband Periodic Endfire Antenna With Bowtie Dipoles

A wideband periodic antenna with bowtie dipoles, fed by a microstrip line, is proposed. A wideband transition from a microstrip line to a parallel strip line (PSL) is utilized to achieve a good differential-fed mechanism. The measurements show that the antenna presents an impedance bandwidth of 51.4% for SWR les 2, an average gain of 4 dBi and stable unidirectional radiation patterns. Its total size is 1.2 times 0.7 lambda² (lambda is the free-space wavelength at the center frequency). The studies of four critical parameters are performed for practical applications.