The Internet of Things is considered to be the next big opportunity, and challenge, for the Internet engineering community, users of technology, companies and society as a whole. It involves connecting embedded devices such as sensors, home appliances, weather stations and even toys to Internet Protocol (IP) based networks. The number of IP-enabled embedded devices is increasing rapidly, and although hard to estimate, will surely outnumber the number of personal computers (PCs) and servers in the future. With the advances made over the past decade in microcontroller,low-power radio, battery and microelectronic technology, the trend in the industry is for smart embedded devices (called smart objects) to become IP-enabled, and an integral part of the latest services on the Internet. These services are no longer cyber, just including data created by humans, but are to become very connected to the physical world around us by including sensor data, the monitoring and control of machines, and other kinds of physical context. We call this latest frontier of the Internet, consisting of wireless low-power embedded devices, the Wireless Embedded Internet. Applications that this new frontier of the Internet enable are critical to the sustainability, efficiency and safety of society and include home and building automation, healthcare, energy efficiency, smart grids and environmental monitoring to name just a few.
標(biāo)簽： Embedded Internet Wireless 6LoWPAN The
上傳時(shí)間： 2020-05-26
上傳用戶：shancjb
For nearly a hundred years telecommunications provided mainly voice services and very low speed data (telegraph and telex). With the advent of the Internet, several data services became mainstream in telecommunications; to the point that voice is becoming an accessory to IP-centric data networks. Today, high-speed data services are already part of our daily lives at work and at home (web surfing, e-mail, virtual private networks, VoIP, virtual meetings, chats...). The demand for high-speed data services will grow even more with the increasing number of people telecommuting.
上傳時(shí)間： 2020-05-27
上傳用戶：shancjb
One of the very first books published on the social impact of the mobile phone was Timo Kopomaa’s The City in Your Pocket: Birth of the Mobile Information Society. The book, published in 2000, was based on research that Kopomaa had under- taken for Nokia and Sonera as part of his doctoral studies in the Centre for Urban and Regional Studies at the Helsinki University of Technology. The first line he writes in the book is peculiar: ‘Mobile communication is not a serious matter’. By this, we assume he is referring to a view of the world that would regard the mobile phone as little more than an unremarkable fact of everyday life – a simple play- thing for the young, or a productivity tool for the business executive and busy parent.
標(biāo)簽： Communications Wireless Mobile and
上傳時(shí)間： 2020-05-30
上傳用戶：shancjb
Wireless means different things to different people. For this book, it refers to the radio systems that provide point-to-point, point-to-multipoint, and Earth-space communications over transmission links that propagate outside buildings through the lower atmosphere. Wireless systems are being built that provide data transmission between computers and other devices on one’s own desk. These are part of the wireless world but not the part where, except for interference perhaps, the atmosphere has any influence. The intent of this book is to provide a description of the physical phenomena that can affect propagation through the atmosphere, present sample measurements and statistics, and provide models that system designers can use to calculate their link budgets and estimate the limitations the atmosphere may place on their design.
標(biāo)簽： Communication Propagation Handbook Wireless for
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
Quality of Service ( QoS ) has always been in a world of its own, but as the technology has been refi ned and has evolved in recent years, QOS usage has increased to the point where it is now considered a necessary part of network design and operation. As with most technologies, large - scale deployments have led to the technology becoming more mature, and QOS is no exception.
標(biāo)簽： QOS-Enabled Networks
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
This paper presents a Hidden Markov Model (HMM)-based speech enhancement method, aiming at reducing non-stationary noise from speech signals. The system is based on the assumption that the speech and the noise are additive and uncorrelated. Cepstral features are used to extract statistical information from both the speech and the noise. A-priori statistical information is collected from long training sequences into ergodic hidden Markov models. Given the ergodic models for the speech and the noise, a compensated speech-noise model is created by means of parallel model combination, using a log-normal approximation. During the compensation, the mean of every mixture in the speech and noise model is stored. The stored means are then used in the enhancement process to create the most likely speech and noise power spectral distributions using the forward algorithm combined with mixture probability. The distributions are used to generate a Wiener filter for every observation. The paper includes a performance evaluation of the speech enhancer for stationary as well as non-stationary noise environment.
標(biāo)簽： Telecommunications Processing Signal for
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
Spread-spectrum communication is a core area within the field of digital communication. Originally used in military networks as countermeasures against the threats of jamming and interception, spread-spectrum systems are now widely used in commercial applications and are part of several wireless and mobile communication standards. Although spread-spectrum communication is a staple topic in textbooks on digital communication, its treatment is usually cursory. This book is designed to provide a more intensive examination of the subject that is suitable for graduate students and practicing engineers with a solid background in the theory of digital communication. As the title indicates, this book stresses principles rather than specific current or planned systems, which are described in manyotherbooks.My goal in this bookis to providea concisebut lucidexplanation of the fundamentals of spread-spectrum systems with an emphasis on theoretical principles.
標(biāo)簽： Spread-Spectrum Communication Systems 2nd
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
When thinking about mobile radio engineers there is a tendency to assume that the engineering function relates solely to the technical aspects of the network, such as the equipment design or the network design. That is certainly a key part of the role of a mobile radio engineer. However,increasinglyengineersarerequiredtointeractwithprofession- als from other divisions. The “complete wireless professional” should know about mobile networks; fixed networks; other types of mobile systems; regulatory and government policy; the requirements of the users; and financial, legal, and marketing issues.
標(biāo)簽： Communications Complete Wireless The
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
When thinking about mobile radio engineers there is a tendency to assume that the engineering function relates solely to the technical aspects of the network, such as the equipment design or the network design. That is certainly a key part of the role of a mobile radio engineer. However,increasinglyengineersarerequiredtointeractwithprofession- als from other divisions.
標(biāo)簽： Communications Professional Complete Wireless The
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
Public telephone operators and new independent wireless operators through- out the world are deploying wireless access in an effort to drastically reduce delivery costs in the most expensive part of the network?the local loop. Available radio technology enables both existing and new entrants to access subscribers in a rapid manner and deliver their basic telephony products and broadband-enhanced services.
標(biāo)簽： Transmission Handbooks Systems Design
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
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