Exemplos de uso de Cognitive radios em Inglês e suas traduções para o Português
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Spectrum sensing based on energy detection for cognitive radios.
Cognitive radios are a promising solution for the spectrum scarcity problem.
On the other hand, in the second case,is considered that the cognitive radios in the network exchange information among them.
Thus, cognitive radios should possess a high degree of reconfigurability, so that they can operate in a very wide frequency range.
Another approach relies on the proper functioning of the cognitive radios, i.e., the channel hopping to make the rendezvous among them. however.
In this context, cognitive radios appear as an appropriate option able to offer an efficient use of the channel, ensuring greater bandwidth to users.
To satisfy spectrum detections the requirements andinterfere little with licensed user, cognitive radios have as its main stage sensing of spectrum radio. .
In the scenario of cognitive radios, cyclostationary analysis techniques have shown to be quite effective in extracting features that can be used in the spectrum sensing.
To make this possible, without interfering or degrading the signals from the licensed users,it is necessary to fulfill four essential requirements of cognitive radios: spectrum sensing, spectrum decision, spectrum sharing, and spectrum mobility.
In this scenario, there is the cognitive radios(crs) technology, which is trying to solve the problem of under-utilization of the spectrum through the process of spectrum sensing.
The electromagnetic spectrum is a precious and scarce natural resource. therefore,a considerable effort is being directed at the development of cognitive radios, capable of sensoring the spectrum and using momentarily available frequency bands in an opportunistic way.
In this work,we are able to analyze cognitive radios network performance in terms of throughput and average delay, considering slotted aloha and carrier sense multiple access(csma) protocols.
Research at INT mainly focuses on the field of mobile communications as well as on digital signal processing as its scientific foundation:Software defined and cognitive radios; Dynamic spectrum management; Efficient, resource-optimized radio transmission; Ultra wide band; Digital signal processing and analysis.
This opportunistic access model requires cognitive radios to switch among channels searching for new opportunities and making contact with their neighbors to exchange the information needed for spectrum management.
These policy objectives relate in particular to the following areas: the digital dividend, short-range devices, air traffic management systems, broadcasting satellite services,software defined radio and cognitive radios, electronic news gathering, scientific services and spectrum requirements for systems such as Galileo.
Concerning the centralized spectrum sensing system, the case in which the cognitive radios send only one decision bit(hard decision) to the fusion center and the case in which the detector send the statistic test(soft decision) are considered.
Cognitive radios were proposed for a better use of radio spectrum, aiming at the use of the radio spectrum not used by spectrum owners, interfering as minimal as possible at transmissions done by spectrum owners.
This paper presents some mac protocols for cognitive radios that aim to control how users make access to the shared medium.
The technology of cognitive radio has been considered a promising solution to this problem.
Spectrum sensing for cognitive radio.
Cognitive radio introduces a new policy for spectrum access in communications systems.
In this context, cognitive radio appears as a more efficient alternative, by providing opportunistic spectrum access, with the maximum bandwidth possible.
Recently, a new technique for spectrum sensing in cognitive radio(cr) networks has been proposed named cooperative power spectral density split cancellation cpsc.
Cognitive radio have emerging as promising technology to tackle the problem of spectrum scarcity by opportunistically exploit the underutilized radio spectrum.
Cognitive radio(cr) have emerged as an alternative to reduce interference and intelligently use the spectrum.
Blind signal search is a technique used in many different types of systems,ranging from cognitive radio to broadcasting applications such as television and radio. .
This work proposes the concept andreports the implementation of the architecture acrof, which stands for adaptive and cognitive radio over fiber.
A study of tv channels(digital and analog)spectrum sensing is developed to cognitive radio.
Recently, an eigenvalue fusion approach for detecting idle subchannels of ofdma signals in the context of centralized cooperative spectrum sensing for cognitive radio(cr) was proposed.
For evaluation, moca is compared by simulations with tcp friendly rate control- cognitive radio(tfrc-cr) under representative scenarios of urban environments.