%0 Journal Article
%T Compact U-Slotted Antenna for Broadband Radar Applications
%A S. Costanzo
%A A. Costanzo
%J Journal of Electrical and Computer Engineering
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/910146
%X The original U-shaped patch antenna is properly modified in this work to provide a compact and broadband antenna configuration with reduced cross-polar effects, well suitable for modern radar applications. The proposed antenna layout is applied to design, realize, and test two different prototypes working at P-band and C-band, typically adopted for ground-penetrating radar. The experimental results successfully demonstrate a large operating bandwidth between 15% and 20%, a significant reduction of size (about half of the standard configuration), and a low cross-polarization level within the operating frequency range. 1. Introduction The new generation radar systems require advanced components and materials [1¨C4] in order to properly exhibit their innovative features [5, 6]. For this motivation, in recent years, most of the classical hardware radar architecture functions have begun to be implemented via software, in order to reduce the costs and the complexity of the entire system [7¨C9]. Antennas often represent the most critical hardware component in the radar system, and the design of the radiating element needs to satisfy several constraints required by the novel applications, especially in terms of bandwidth [10¨C14] and quality of the radiation pattern, while guaranteeing, at the same time, a compact configuration. Microstrip patch antennas are largely employed in radar systems due to their low costs and easy manufacturing, low profile, light weight, and good strength, but the use of standard single-layer microstrip patch is not suitable for most radar applications, mainly due to its narrowband behavior. Additional resonant elements, such as slots, may be included in the radiating surface in order to enhance the bandwidth. The U-slot configuration is typically adopted at this aim, as the multiple resonances introduced by the slot allow it to produce a unique wideband response. Various examples exist in the literature for the standard U-slot patch antenna configuration. In [15], a compact U-slotted microstrip patch, performing a wideband behavior, has been presented, and in [16] an example of multiband U-slot antenna has been proposed. Even if all existing works show that U-slot configuration yields good results in terms of bandwidth and compactness, the additive resonances significantly disturb the main flow of the surface current, thus increasing the cross-polarization level. As a consequence of this, the useful radiation bandwidth of standard U-slot configuration is significantly reduced with respect to that achieved in terms of return loss
%U http://www.hindawi.com/journals/jece/2013/910146/