A High-Gain Endfire Periodic Leaky-Wave Antenna Using DSPSL-Based Rhombic Element

An endfire periodic leaky-wave antenna (LWA) with high gain is presented in this communication, which consists of a series of rhombic elements based on double-sided parallel stripline (DSPSL). The endfire mechanism of the proposed antenna is illustrated by the phase difference of the far field of each arm in the rhombic element. Meanwhile, a tradeoff between the tilted angle
$\theta _{0}$
and the width
$w$
is found, which assures an optimum transverse aperture for achieving high-gain endfire radiation. Moreover, the improved Hansen–Woodyard (IHW) condition is applied to predict the optimum endfire phase constant. Finally, a prototype is fabricated and tested. The maximum endfire gain of 19.8 dBi is measured at 11.4 GHz, which is close to the simulated and predicted results. The proposed periodic rhombic antenna provides more choice for the modern communication system.