A High-Gain Single-Layered Circularly Polarized Spiral Series-Fed Patch Antenna Array

This paper shows a high-gain single-layered circularly polarized 2-dimensional (2D) series-fed patch antenna array. One fundamental problem of leaky-wave antennas and series-fed antennas is that the efficiency can degrade quickly when the antenna is designed for higher gain with a larger size. This is due to the fact that the leakage rate needs to be reduced while the loss rates remain constant. We will demonstrate that with the spiral configuration, this issue can be easily resolved with one simple alteration of the feeding, namely the addition of a radial power divider in the array center feed.