Search results for "Figur"
showing 10 items of 1122 documents
An FPGA-Based Software Defined Radio Platform for the 2.4GHz ISM Band
2006
A prototype of a Software Defined Radio (SDR) platform has been successfully designed and tested implementing a reconfigurable IEEE 802.11 and ZigBee receiver. The system exploits the reconfiguration capability of an FPGA for implementing a number of receiver configurations that share the same RF front-end. Configurations can be switched at run time, or can share the available logic and radio resource.
HEMT for low-noise microwaves: CAD-oriented performance evaluation
1995
This paper shows how a graphic processing of low-noise HEMT's small signal parameters, allows evaluating and comparing the actual performance obtainable in front-end applications. HEMT's tradeoff charts which solve tradeoffs among the basic low-noise amplifier performance are reported. Figures of merit for microwave low-noise HEMT which represent a fast way of evaluating HEMT in actual working conditions and of selecting the proper transistor, are defined. As an example, the tradeoff charts and the figures of merit of two HEMT's (Fujitsu FHR02FH, Sony 2SK677) and a pseudomorphic-HEMT (Celeritek CFB001-03) are reported and compared with the data sheets. © 1995, IEEE. All rights reserved.
Reconfigurable dualband antenna module with integrated high voltage charge pump and digital analog converter
2014
Integration of a reconfigurable antenna module for handheld applications employing a set of novel technologies is demonstrated. A low profile dualband hybrid dielectric resonator antenna (DRA) based on glass-ceramics and a tunable matching network (TMN) based on ferroelectric varactors with a maximum biasing of 90V form a reconfigurable antenna module. The control of the antenna module is performed by a 120V CMOS high voltage (HV) charge pump with an 8-bit digital analog (D/A) converter generated from a 3.7V battery. Adaptive impedance matching at the lower band of 1.9 GHz is carried out by the TMN when the dualband antenna is exposed to different operation scenarios. Meanwhile, the upper b…
Economic benefits of the use of a PV plants reconfiguration systems
2015
This paper shows the economic convenience of the application of a reconfiguration system for photovoltaic plants, considering the incentives system in different Countries. The reconfiguration is an alternative to the Distributed Maximum Power Point Tracking, DMPPT, technique used to overcome the mismatch problem in Photovoltaic, PV, plants. The reconfiguration techniques employ a microprocessor-based system that modifies the layout of the PV plant by physically changing the connections among modules. After having presented the working principle of the PV reconfiguration system allowing the improvement of the efficiency of the same plant and the relevant installation, the main strength and w…
Consideration Regarding the Configuration of the Resources and Modeling the Manufacturing Work Cell
2015
This paper is presented the concept of developing a generic reference architecture model for the specification, development, control and reconfiguration of a manufacturing enterprise at a work cell level. It is described a generic system architecture for FMS; there is also briefly explained how to configure the different resource modules that actually control the tasks of the physical device and put together a work cell consisting of other FMS resources. Using the principles of distributed object technology there could be implemented each resource in the work cell as a distributed object. Finally, an example on building a FMS using a hierarchical approach is presented.
Different Wings Flowfields Interaction on the Wing-Propeller Coupling
1997
A high-portability numerical technique based on the method of free wake analysis (FWA) is described that analyzes the interference between an aircraft propeller and a wing having different planforms and computes the influence of the wing aerodynamic field on the propeller performance. For an isolated propeller and wing, the models employed are based on the FWA and Prandtl theory, respectively. The performance of the propeller in the presence of the wing is related to the wing angle of attack and to the variation of wing circulation and the corresponding induced velocity at the propeller disk. A numerical model, previously and successfully used, was implemented to account for the effects of …
DC link voltage swinging and load current unbalance in fault tolerant VSI. overview and compensation strategies
2015
The topic of this paper is the discussion on the performance of a three-phase fault tolerant inverter with particular attention to the underrated aspect of current unbalances occurring due to the DC link voltage fluctuates after the inverter reconfiguration. Capacitor voltage unbalance affects not only the average output voltage of the inverter, but also its performance. In fact, the inverter performance depends on the fluctuating DC-link voltage components rather than on the average DC-link voltage. After a brief analysis of the voltage fluctuation phenomena resulting from fault tolerant configuration and their effect on load current unbalance, the Authors consider different compensating p…
Reconfigurable digital instrumentation based on FPGA
2004
A novel application of FPGA to realize digital test equipment is proposed. It takes advantage of the dynamic reconfigurability of FPGAs so easily tailoring custom test functions in the same instrument. This results in high effective, compact and low cost instruments.
Production planning in reconfigurable enterprises and reconfigurable production systems
2005
Reconfigurable enterprises and reconfigurable production systems represent nowadays one of the key responses towards the organisational and manufacturing needs arising in the new era known as mass customization. The paper proposes an Agent Based approach for the production planning activities in reconfigurable enterprises, characterized by complex, articulated and geographically distributed production capacities contended by many product families and composed by reconfigurable production systems that allow quick adjustment of production capacity and functionality consenting to manufacture different products of the same part family.
2-D approach to the analysis of semianechoic chambers using a hybrid technique
2003
Semianechoic chambers are the most widely used emplacements for electromagnetic compatibility (EMC) tests. In this work a new and efficient technique for the analysis of 2-D simplified model of a chamber with arbitrary absorber is introduced and validated Some advanced results are presented, and a 2-D figure of merit for studying the overall behaviour of the chamber is proposed.