a new multiple c- slotted microstrip patch antenna is proposed.  a patch antenna is a wide-beam narrowband antenna. microstrip patch antenna consist of a very thin metallic strip (patch) placed a small fraction of a wavelength above a ground plane. the patch can be designed in any possible shape and normally made by conducting material copper or gold. this paper presents design of a c- slotted ...

We present a system for automatically building 3-D maps of underwater terrain fusing visual data from a single camera with range data from multibeam sonar. The six-degree of freedom location of the camera relative to the navigation frame is derived as part of the mapping process, as are the attitude offsets of the multibeam head and the on-board velocity sensor. The system uses pose graph optim...

AIMS The aim of this study was to validate and assess the feasibility of a previously described method using multibeam high-pulse repetition frequency (HPRF) colour Doppler to quantify the vena contracta area (VCA) in aortic regurgitation (AR). METHODS Twenty-nine patients with mild to severe AR were studied. Regurgitant volume and fraction measured by magnetic resonance imaging (MRI) were us...

It has recently been shown [Weber, T. C. et al. (2007). "Acoustic propagation through clustered bubble clouds," IEEE J. Ocean. Eng. 32, 513-523] that gas bubble clustering plays a role in determining the acoustic field characteristics of bubbly fluids. In particular, it has been shown that clustering changes the bubble-induced attenuation as well as the ping-to-ping variability in the acoustic ...

Over the last ten years, the high-resolution marine geophysical survey field has witnessed significant advances in survey investigation equipment. New equipment is based on acoustic, optical, electrical, and magnetic sensors. This paper will focus on the use of quantitative acoustic methods for the high-resolution mapping of the seafloor for archaeological heritage management. In particular mul...

We analyze the improvements obtained in wireless infrared (IR) communication links when one replaces traditional single-element receivers by imaging receivers and diffuse transmitters by multibeam (quasi-diffuse) transmitters. This paper addresses both line-of-sight (LOS) and nonline-of-sight (non-LOS) IR links. We quantify link performance in terms of the transmitter power required to achieve ...

This paper describes a pose-based underwater 3D Simultaneous Localization and Mapping (SLAM) using a multibeam echosounder to produce high consistency underwater maps. The proposed algorithm compounds swath profiles of the seafloor with dead reckoning localization to build surface patches (i.e., point clouds). An Iterative Closest Point (ICP) with a probabilistic implementation is then used to ...

In this paper we consider a set of portable stations which communicate with a basestation equipped with a smart antenna operating in multibeam packet-switched SDMA mode. We assume that the system operates using time division du-plexing (TDD) and focus on the problem of access to the stations by the basestation in the forward link direction. A polling protocol is used which permits eecient acces...

This paper is devoted to the study of cellular communications using aerial platforms (APs). A set of key equations is derived that quantify the coverage area on the ground as a function of AP elevation, the operation of the adaptive multibeam antenna on the AP, and the formulation of contiguous terrestrial cells and their shapes. Specifically, we consider the deployment of an AP to provide terr...

The U-slot micro-strip patch antennas were originally developed for bandwidth broadening applications. This study presents a transmission line feed to modify the U-slot stacked rectangular micro-strip patch antenna for Ultra-Wide Band (UWB) communications. The modified antenna has a U-cut loaded with parallel slits and corner slots and is printed on a dielectric substrate of FR4 with relative p...