An Eight-element Dielectric Rod Antenna Array Integrated to a Substrate Integrated Waveguide Feed for Wide Band Applications

Dielectric rod antenna elements have numerous advantages over conventional waveguide and horn antenna elements. They have low loss performance, and provide broadband input match, high mutual decoupling efficiency, and low cost manufacturing. Additionally, the radiation pattern of the dielectric rod antenna is almost frequency independent. However, its feeding is generally a challenge. This paper demonstrates a novel ultra-wide band (UWB) eight-element dielectric rod antenna array fed by a wide band Substrate Integrated Waveguide (SIW) structure. The eight-way feed network is compact and has less than 1.1 dB insertion loss, and only +/- 0.9 dB and +/- 4 degrees amplitude and phase imbalance, respectively. The paper exhibits the design of a low cost and compact dual layer dielectric rod array antenna that covers over 40% bandwidth at X-band. This array has a good input match, almost constant radiation pattern with a gain of 14.5 +/- 2 dB over the frequency band, low dispersion, and low squint performance and only occupies 10cmx9cm.