CTS Antenna Array Optimization using Passive Corrugated Ground Plane

In this paper, the usage of passive corrugations to improve the performances of continuous transverse stub (CTS) arrays is investigated. Corrugations are employed as a secondary radiation source to reemit surface energy and to modulate surface waves at the antenna surface. Thanks to this effect, we demonstrate that the number of radiating slots of the CTS array can be halved maintaining the electrical performances unchanged (gain, bandwidth, and radiation pattern). The new array has a simplified feeding network, is more compact and lighter than the original configuration. Besides, the manufacturing complexity and cost of the new configuration are significantly reduced.

I. Introduction

Since their invention in the early 1990s Continuous Transverse Stub (CTS) planar arrays [1] have attracted considerable attention due to their advantage of compact size, low loss, low cross-polarization and high efficiency. To guarantee high gain and power handling capability most of the CTS antennas are designed using metal waveguides. Unfortunately, the large feed network has a negative impact on antenna size and weight. In this paper, we propose the use of a corrugated ground plane to halve the number of radiating slots of the CTS array maintaining unchanged the electric performances (gain, bandwidth, and radiation pattern). A reduction by half of the number of radiating elements has a significant impact on the complexity of the feeding network. To demonstrate the validity of the proposed idea, the CTS array described in [2] has been taken as a reference. Corrugations have been used to halve the number of radiating slots and the feeding network has been redesigned. The weight and complexity of the analyzed structure are considerably reduced. The thickness of the proposed CTS array is also decreased by about 20% to the original configuration maintaining the electrical performances unchanged.