1-D Scanning Arrays on Dense Dielectrics Using PCS-EBG Technology

We show how the design of integrated arrays can significantly benefit from planar circularly symmetric (PCS) electromagnetic band gap (EBG) structures. Using this technology, a phased array that scans up to 40° in one dimension and that is characterized by relatively large bandwidth (BW ≈ 15%) is designed, manufactured and tested. The specific...

On the Optimal Radiation Bandwidth of Printed Slot Antennas Surrounded by EBGs

This paper describes a design strategy to achieve the maximum bandwidth and efficiency for a printed slot antenna surrounded by EBGs. First the dielectric constant and the thickness of the dielectric slab that guarantees an acceptable front to back radiation ratio is identified. Then electromagnetic bandgap (EBG) structures are designed to...

Application of EBG Structures at Sub-Array Level

Low efficiency and pattern degradation are specific problems encountered in phased array designs based on integrated technology, as for example used in lowprofile radar applications. These problems are largely due to the excitation of surface waves (SW). It was demonstrated in earlier work that Electromagnetic Band Gap (EBG) technology can...

Enhanced Antenna Performances Using Planar Circularly Symmetric EBG's

Planar circularly symmetric (PCS) electromagnetic band-gap (EBG) substrates have recently been proposed to suppress surface waves (Llombart, N. et al., 2004). The application of PCS-EBG to reduce the surface waves excited by an antenna printed on a dielectric slab is discussed. The study starts from a reference microstrip-excited, slot-coupled...

Planar Circularly Symmetric EBG Structures for Reducing Surface Waves in Printed Antennas

This paper discusses the design and analysis of planar circularly symmetric (PCS) electromagnetic band gap (EBG) structures for reducing the surface waves excited by printed antennas on dense dielectric substrates. The key advantage of the circularly symmetric geometries is that a surface wave generated by a source located at its center...

Bandwidth, efficiency and directivity enhancement of printed antenna performance using planar circularly symmetric EBGs

Planar Circularly Symmetric (PCS) Electromagnetic Band-Gap (EBG) substrates have been recently proposed to suppress the surface waves in printed technology [1] [2]. The major advantage of the PCS-EBGs with respect to structures based on vertical pins [3] [4] is the fabrication simplicity since the dielectric slabs do not need to be perforated....

On the use of planar EBGs in One Dimensional (1D) scanning printed arrays

In a companion paper [1] presented in this same conference, the use of Planar Circularly Symmetric (PCS) Electromagnetic Band-Gap (EBG) structures for optimizing the performances of single antenna elements is discussed. A completely planar antenna with 20% of bandwidth which does not suffer from surface wave effects is presented. The key...

Planar Circularly Symmetric EBG's to Improve the Isolation of Array Elements

A trade off has to be made between bandwidth and isolation of array elements when designing phased arrays. When the isolation is achieved via a PCS-EBG that is aimed at reducing the TM00 mode only, the reduction of bandwidth could be even more important rather than the one obtained when using a more standard cavity backing. This is due to the...

Bandwidth, Efficiency and Directivity Enhancement of Printed Antenna Performance Using Planar Circularly Symmetric EBGs

Planar Circularly Symmetric (PCS) Electromagnetic Band-Gap (EBG) substrates have been recently proposed to suppress the surface waves in printed technology [1] [2]. The major advantage of the PCS-EBGs with respect to structures based on vertical pins [3] [4] is the fabrication simplicity since the dielectric slabs do not need to be perforated....

Planar circularly symmetric EBG structures - Design and analysis

This paper deals with the design and the analysis of planar circularly symmetric (PCS) EBG structures. The analysis is concentrated on TM excitations. To obtain simple design rules for the PCS-EBG's, an equivalence is established between 2D-EBG's and PCS-EBG's. he dispersion equations are investigated first. The 2D problems are studied by means...

On the assessment of shooting sounds: Loudness-level weightings versus A- and C-weighted sound exposure levels (L)

As an alternative to the A-weighted sound exposure level (ASEL) Schomer et al. [J. Acoust. Soc. Am. 110, 2390-2397 (2001)] used the equal-loudness level contours as a dynamic filter to determine the loudness-level-weighted sound exposure level (LLSEL). From their analyses they concluded that the LLSEL better orders and assesses traffic and...

Sea spray aerosol production from waves breaking in the surf zone

Sea spray aerosol is a product of wave breaking. A very strong source of this aerosol is the surf zone. In this sense, measurements in the surf zone can be suitable for the assessment of the contributions of the various spray production mechanisms to the total concentrations. At present, a comprehensive data set for performing such measurements...

Studies on a surface acoustic wave (SAW) dosimeter sensor for organophosphorous nerve agents

As a follow-up of previous work on a Surface Acoustic Wave (SAW) sensor for nerve agents, irreversible response effects have been studied in more detail. Surface analytical studies indicated that degradation products are responsible for the effects observed. In addition it was tried to explore these effects for the development of a nerve agent...