Journal of Green Engineering- Special Issue | Cognitive Radio and the Application to Green Communications: Technical, Economic, and Regulatory Viewpoints

Editor

River Publishers

Fecha de publicaci�n

2012

Idioma

Ingl�s

ISBN 10

8792329330

ISBN 13

9788792329332

Encuadernaci�n

Taschenbuch

Estado

Neu

Dimensiones

Peso

225 gramos

Cat�logos de vendedores

B�cher

Acerca de

Sinopsis

Demand for wireless data exchange is perpetually increasing, leading to pressure on deployed wireless capacity. As systems enhance their spectral efficiency to attempt to address this, evermore complex processing techniques are being employed. Such techniques increase power consumption, leading to greater heat output from processers in network elements and increasing powered cooling. Moreover, the requirement for wideband linearity of radio frequency circuitry in state-of-the-art OFDM systems, twinned with high transmission power capability on the network side and the inefficiencies of components when operating at such limits, leads to greater inefficiency hence further heat power output and the need for greater cooling. All of these ingredients significantly affect the power consumption of communications equipment. Indeed, merely considering raw transmission power, the Shannon-Hartley theorem implies that necessary transmission power increases exponentially with required capacity.Such power consumption issues can be mitigated through cognitive radio (CR) techniques. The use of greater bandwidths through CR and in some cases the aggregation of bandwidths, as well as the opportunistic use of spectrum of more appropriate propagation characteristics or with better interference management, can reduce necessary transmission power for devices and systems. Moreover, CR techniques may achieve greater spatial/temporal awareness of connectivity options and their inherent power consumptions, as well as the power consumptions of chosen radio access characteristics. They might be able to use this awareness to dynamically switch to connections that better manage loads and interference, or might be able to minimize the power consumption of radio frequency circuitry through switching radio access technique given a required traffic load. At a simpler level, they may be able to appropriately select nearer connectivity options minimizing path loss/shadowing hence necessary transmission power, in consideration of experienced/predicted traffic loads and channel characteristics. Such capabilities are particularly relevant considering that, at least in terms of the transmission power to from-the-socket power consumption ratio, lower power equipment such as wireless LAN access points achieves far better efficiency than higher-power equipment such as macro-cell base stations. This manifestation is not only because of favorable path loss characteristics, but also because of the better efficiencies of the lower power components in such access points.CR might also assist in making other areas of life more environmentally friendly. The application of CR to intelligent transportation, for example, facilitating the sharing of information in a timely manner and with appropriate data rates among vehicles and between vehicles and roadside infrastructure through enhancing the capabilities of systems such as IEEE 802.11p, could lead to the better management of traffic signals and better collaborative automated management of traffic speeds, limiting unnecessary vehicular start/stop cycles and greatly reducing the burning of fossil fuels. Moreover, the presence of CR capability in a wide range of future machines will facilitate those machines talking to each other more ubiquitously than today. Such machine-to-machine communications could greatly enhance the energy efficiency of everyday living. One example of this is smart grids and smart homes, facilitating the usage of energy locally, only when needed, andcatering for the integration, better prediction of and capitalization from renewable resources. Among other benefits, such solutions would decrease wastage in the home through better management of appliances and heating/cooling options.

Rese�a del editor

Demand for wireless data exchange is perpetually increasing, leading to pressure on deployed wireless capacity. As systems enhance their spectral efficiency to attempt to address this, evermore complex processing techniques are being employed. Such techniques increase power consumption, leading to greater heat output from processers in network elements and increasing powered cooling. Moreover, the requirement for wideband linearity of radio frequency circuitry in state-of-the-art OFDM systems, twinned with high transmission power capability on the network side and the inefficiencies of components when operating at such limits, leads to greater inefficiency hence further heat power output and the need for greater cooling. All of these ingredients significantly affect the power consumption of communications equipment. Indeed, merely considering raw transmission power, the Shannon-Hartley theorem implies that necessary transmission power increases exponentially with required capacity. Such power consumption issues can be mitigated through cognitive radio (CR) techniques. The use of greater bandwidths through CR and in some cases the aggregation of bandwidths, as well as the opportunistic use of spectrum of more appropriate propagation characteristics or with better interference management, can reduce necessary transmission power for devices and systems. Moreover, CR techniques may achieve greater spatial/temporal awareness of connectivity options and their inherent power consumptions, as well as the power consumptions of chosen radio access characteristics. They might be able to use this awareness to dynamically switch to connections that better manage loads and interference, or might be able to minimize the power consumption of radio frequency circuitry through switching radio access technique given a required traffic load. At a simpler level, they may be able to appropriately select nearer connectivity options minimizing path loss/shadowing hence necessary transmission power, in consideration of experienced/predicted traffic loads and channel characteristics. Such capabilities are particularly relevant considering that, at least in terms of the transmission power to from-the-socket power consumption ratio, lower power equipment such as wireless LAN access points achieves far better efficiency than higher-power equipment such as macro-cell base stations. This manifestation is not only because of favorable path loss characteristics, but also because of the better efficiencies of the lower power components in such access points. CR might also assist in making other areas of life more environmentally friendly. The application of CR to intelligent transportation, for example, facilitating the sharing of information in a timely manner and with appropriate data rates among vehicles and between vehicles and roadside infrastructure through enhancing the capabilities of systems such as IEEE 802.11p, could lead to the better management of traffic signals and better collaborative automated management of traffic speeds, limiting unnecessary vehicular start/stop cycles and greatly reducing the burning of fossil fuels. Moreover, the presence of CR capability in a wide range of future machines will facilitate those machines talking to each other more ubiquitously than today. Such machine-to-machine communications could greatly enhance the energy efficiency of everyday living. One example of this is smart grids and smart homes, facilitating the usage of energy locally, only when needed, and catering for the integration, better prediction of and capitalization from renewable resources. Among other benefits, such solutions would decrease wastage in the home through better management of appliances and heating/cooling options.

"Sobre este t�tulo" puede pertenecer a otra edici�n de este libro.

Descripci�n de la librer�a

preigu betreibt einen Onlineversandhandel mit �ber 1 Mio. Produkten in verschiedenen Sortimenten. Das Kernsortiment besteht aus B�chern, Medien und Spielwaren. Ein gelungenes Einkaufserlebnis ist das Ziel einer jeden Bestellung bei preigu, denn der Kunde und seine Zufriedenheit stehen an erster Stelle. preigu setzt daher auf einen kompetenten Kundenservice, funktionierende Prozesse und schnelle Reaktion.

Ver la p�gina web de la librer�a

Informaci�n empresarial del vendedor

preigu GmbH & Co. KG
Lengericher Landstra�e 19, Osnabr�ck, 49078, Germany

Condiciones de venta y env�o

Condiciones de venta

Standard Business Terms and customer information

I. Standard business terms

� 1 Basic provisions

(1) The following terms and conditions of business apply for all contracts concluded with us as the supplier (preigu GmbH & Co. KG) via the websites AbeBooks and/or ZVAB. Unless otherwise agreed, the inclusion of your own terms and conditions is explicitly rejected.

(2) A ?consumer' in the sense of the following regulations is every natural person who concludes a legal transaction which, to an overwh...

M�s informaci�n

Derecho al desistimiento

Instructions for revocation

Right of withdrawal for the sale of goods

Revocation right for consumers
(A ‘consumer' is any natural person who concludes a legal transaction which, to an overwhelming extent, cannot be attributed to either his commercial or independent professional activities.)

Instructions for revocation

Revocation right
You have the right to revoke this contract within 14 days without specifying any reasons.
The revocation period is 14 days with effect from the day,

on which you or a third party nominated by you, which is not the carrier, had taken possession of the products, provided you had ordered one or more products within the scope of a standard order and this/these product/products is/are delivered uniformly;
on which you or a third party nominated by you, which is not the carrier, had taken possession of the last product, provided you had ordered several products within the scope of a standard order and these products are delivered separately;
on which you or a third party nominated by you, which is not the carrier, had taken possession of the last part delivery or the last unit, provided you had ordered a product, which is delivered in several part deliveries or units;

To exercise your right of withdrawal, you must inform us (preigu GmbH & Co. KG, Lengericher Landstr. 19, 49078 Osnabr�ck, Telephone number: +49 (0) 541 / 580 72 84, E-Mail address: mail@preigu.de) by means of a clear declaration (e.g. a letter sent by post, or an e-mail) of your decision to withdraw from this contract. You can use the attached model withdrawal form for this purpose, which is, however, not mandatory.

You can also exercise your right of withdrawal online by clicking on a button labelled accordingly (such as ‘Withdraw from contract' or similar) on the AbeBooks/ZVAB website. If you use this online function, you will immediately receive a confirmation of receipt on a durable medium (e.g. via email) containing information on the content of the withdrawal notice, as well as the date and time of its receipt.

In order to safeguard the revocation period, it is sufficient that you send the notification about the exercise of the revocation right before the expiry of the revocation period.

Consequences of the revocation

If you revoke this contract, we shall repay all the payments, which we received from you, including the delivery costs (with the exception of additional costs, which arise from that fact that you selected a form of delivery other than the most reasonable standard delivery offered by us), immediately and at the latest within 14 days from the day on which we received the notification about the revocation of this contract from you. We use the same means of payment, which you had originally used during the original transaction, for this repayment unless expressly agreed otherwise with you; you will not be charged any fees owing to this repayment.

We can refuse the repayment until the products are returned to us or until you have furnished evidence that you have sent the products back to us, depending on whichever is earlier.

You must return or transfer the products to us immediately and, in any case, at the latest within 14 days with effect from the day on which you inform us of the revocation of this contract. The deadline is maintained if you send the products before the expiry of the 14 day deadline.

You bear the direct costs for returning the products.

You must pay for any depreciation of the products only if this depreciation can be attributed to any handling with you that was not necessary for checking the condition, features and functionality of the products.

Criteria for exclusion or expiry

The revocation right is not available for contracts

for delivery of products, which are not prefabricated and for whose manufacturing an individual selection or stipulation by the consumer is important or which are clearly tailored to the personal requirements of the consumer;
for delivery of products, which can spoil quickly or whose use-by date would be exceeded quickly;
for delivery of alcoholic drinks, whose price was agreed at the time of concluding the contract, which however can be delivered 30 days after the conclusion of the contract at the earliest and whose current value depends on the fluctuations in the market, on which the entrepreneur has no influence;
for delivery of newspapers, periodicals or magazines with the exception of subscription contracts. The revocation right expires prematurely in case of contracts
for delivery of sealed products, which are not suitable for return for reasons of health protection or hygiene if their seal has been removed after the delivery;
for delivery of products if they have been mixed inseparably with other goods after the delivery, owing to their condition;
for delivery of sound or video recording or computer software in a sealed package if the seal has been removed after the delivery.

Specimen - revocation form

(If you wish to revoke the contract, please fill up this form and send it back to us.)

To preigu GmbH & Co. KG, Lengericher Landstr. 19, 49078 Osnabr�ck, Email address: mail@preigu.de :
I/we () herewith revoke the contract concluded by me/ us () regarding the purchase of the following products ()/
the provision of the following service ()
Ordered on ()/ received on ()
Name of the consumer(s)
Address of the consumer(s)
Signature of the consumer(s) (only in case of a notification on paper)
Date

(*) Cross out the incorrect option.

Condiciones de env�o

Tarifas de env�o de Alemania a Estados Unidos de America

Tarifas de env�o de Alemania a Estados Unidos de America
Cantidad del pedido	De 60 a 60 d�as h�biles	De 60 a 60 d�as h�biles
Primer art�culo	EUR 70.00	EUR 70.00

Los plazos de entrega los establecen los vendedores y var�an seg�n el transportista y la ubicaci�n. Los pedidos que pasan por la aduana pueden sufrir retrasos y los compradores son responsables de los aranceles o tarifas asociadas. Los vendedores pueden ponerse en contacto con usted en relaci�n con cargos adicionales para cubrir cualquier aumento en los costes de env�o de los art�culos.

Informaci�n detallada sobre el vendedor