Alexandre M. de Oliveira

A Palm Tree Antipodal Vivaldi Antenna With Exponential Slot Edge for Improved Radiation Pattern

This letter presents an Exponential Slot Edge Antipodal Vivaldi Antenna (ESE-AVA), with improved radiative features as compared to the conventional Antipodal Vivaldi Antenna (AVA) design. It extends the low-end bandwidth limitation, mitigates the side and back lobe levels, corrects squint effect, and increases its main lobe gain. In order to confirm those features, a comparative study among the ESE-AVA, the low directivity conventional AVA and two popular modifications, regular slot edge (RSE) and the tapered slot edge (TSE) AVA is performed. A comparison between AVA and the proposed ESE-AVA at 6 GHz shows an improved gain of 8.3 dB, -15.5 dB of Side Lobe Level (SLL), and 0 degrees of main lobe squint (MLS), in contrast with 5 dB of gain, - 5 dB of SLL, and 5 degrees of MLS in the conventional AVA. By comparing the ESE-AVA with RSE-AVA and TSE-AVA, it was observed that its notches in exponential shape, similar to open the main radiator, besides mitigating the SLL also directs the E-fields distributions towards the main lobe. It reflects into a main lobe gain improvement.

A CMOS UWB pulse beamforming transmitter with Vivaldi array antenna for vital signals monitoring applications

This paper presents a new beamforming transmitter, Ultra Wide Band (UWB) pulse generator for contactless radar monitoring applications of vital signals. The system consists of a programmable delay circuit (PDC or τ), UWB pulse generator circuit and an array of Vivaldi planar antennas. Also, a new CMOS PDC controller is developed in order to provide pulse beamforming. The circuit was designed using 0.18μm CMOS process and the planar antenna array was designed with copper and FR-4 substrate. Spice circuit simulations show the generation of pulses with 136mVpp amplitudes and 350ps width. The generated pulse spectrum complies with the Federal Communications Commission (FCC) spectrum mask in the 6-10GHz range. The dynamic energy consumption is around 0.4pJ per pulse using 2V power supply at pulse repetition rate (PRR) of 100MHz. Electromagnetic simulations using CST MW 2010 shows the Main Lobe with an average magnitude of 12dBi, 30° × 32° angular width, and a beam steering between -15° and +25° for θ, and between -20° and +20° for the φ angles. This system can be applied to human monitoring in hospitals, ports and airports, industrial plants - like refineries and oil platforms - and military units as well.

Performance indicators: A mobile solution to identify legacies in mega events

This paper presents a user-centered mobile solution to evaluate the performance and success of the services infrastructure at the level of Urban Mobility, Tourism, Airports (Air Transport), Stadium (Arenas) and security in mega events. This infrastructure is noted from the perspective of legacies and its impact is evaluated through a collaborative process between the KPI, as a tool installed on each mobile device, and the end user. This project is financed by the National Council for Scientific and Technological Development (CNPq) and aims to identify the relation between the values of investments applied to 2014 FIFA World CUP and the dimension of the resulting legacies.

Optical Character Recognition and Zigbee Wireless Communication for AMR: Conclusive Project

A detailed description of an automated metering reading system development is presented. The project includes visual computing - VSN (Visual Sensor Network), techniques for image treatment implemented at an OCR (Optical Char- acter Recognition) and data treatment through a service-oriented software structure. The elements of image acquisition and treatment are composed of an embedded system which associates CCD (Charge-coupled device), DSP (Digital Signal Process) and ZigBee Modules of communication. The control interfaces start with a ZigBee-Ethernet communication module and a service-oriented middleware in charge of the abstraction and treatment of the management data of the AMR (Automation Meter Reading) for the application layer. With this system, ZigBee sensors are integrated and form a wireless mesh; the information is then sent to a concentrator. An important characteristic is that this system can be adapted to any kind of energy meter and water meter in Brazil. The total cost of this system is about USD

CPSensys: Events monitoring and control with flexibility and mobility

66.00 and it is of easy imple- mentation and operation.

Cloud Application Platform as a Service in Educational Environments

This paper presents the CPSensys application, a new platform for smart houses monitoring using mobile devices. The application favors components heterogeneity and the flexibility in controlling static events. For the final version, the use of a dynamic and proactive model is expected. The interfaces are highly intuitive and allow the user to have a greater interaction with the hardware and transparency in communication procedures.

State of the art: integrating services for mega events

This paper describes a proposal for developing an architecture for Educational Cloud based on OpenStack framework, Service Composition techniques and Semantic Web to create virtualized environments with specific features for teaching and researching environments, through the study of recent patents correlated to this system. The creation and management of the architecture and its virtualized environment are conducted through a system of service composition. Services are made available as a catalogue and their access is limited by the users profile type (student, teacher, or researcher). The results shown in this article are limited to the presentation and description of the system logic architecture and modeling.

A complete CMOS UWB Timed-Array Transmitter with a 3D vivaldi antenna array for electronic high-resolution beam spatial scanning

This paper describes the state of the art of a simplified model for integration of services in mega events. The project context, which was financed by the National Research Council – CNPq, is divided into six major areas or functional groups: Urban Mobility, Tourism, Airports, Security, Energy and Telecommunications. The proposal is described in layers, as an infrastructure model of integration and services evaluation, describing its main layers and interaction processes. The proposal described in this paper is restricted to the telecommunication subproject, however, in the modeling of the scenario for the study case, it was necessary to considerate requirements and variables that are common to all subprojects. In the specification process of these requirements, we noticed important processes that interact with some sectors in the city of Sao Paulo, however, in the mean time, we noticed some failures regarding the integration and collaboration performed by administrators elements of stadiums as main focus in the mega event and part of our case study. Currently, the proposal is in its first version as open software for the evaluation of the services quality and the mega event infrastructure through the use of performance indicators.

A CMOS UWB transmitter with Vivaldi Array for Ultra-fast Beam steering microwave radar

We present a new Ultra Wide Band (UWB) Timed-Array Transmitter System with Beamforming capability for high-resolution remote acquisition of vital signals. The system consists of four identical channels, where each is formed of a serial topology with three modules: programmable delay circuit (PDC or τ), a novel UWB 5th Gaussian Derivative order pulse generator circuit (PG), and a planar Vivaldi antenna. The circuit was designed using 0.18μm CMOS standard process and the planar antenna array was designed with film-conductor on Rogers RO3206 substrate. Spice simulations results showed the pulse generation with 104 mVpp amplitude and 500 ps width. The power consumption is 543 μW, and energy consumption 0.27 pJ per pulse using a 2V power supply at a pulse repetition rate (PRR) of 100 MHz. Electromagnetic simulations results, using CST Microwave (MW) Studio 2011, showed the main lobe radiation with a gain maximum of 13.2 dB, 35.5° × 36.7° angular width, and a beam steering between 17° and -11° for azimuthal (θ) angles and 17° and -18° for elevation (φ) angles at the center frequency of 6 GHz.

Simulation and manufacturing of a miniaturized exponential UWB TEM horn antenna for UWB radar applications

This work presents a new Ultra Wide Band (UWB) beamforming fifth-order derivative Gaussian pulse transmitter with dual small Vivaldi antennas for remote acquisition of vital signals in impulse radar applications. The system consists of a programmable delay circuit (PDC or τ), a UWB pulse generator (PG) circuit and an array of two Vivaldi planar antennas. The circuits is designed using the 0.18µm CMOS IBM process. Spice simulations show the pulse generation with 90mVpp amplitude and 300ps width. The average power consumption is 120µW per pulse, using a 2V power supply at a pulse repetition rate (PRR) of 100MHz. Full tridimensional electromagnetic simulations, using CST MWS, show the main lobe radiation with a gain of 5.5dB, and a beam steering between 20o and -17.5o for azimuthal (θ) angles at the center frequency of 7.5GHz.