One traditional view of how wireless networks evolve is of a continuous, inevitable progres- sion to higher link speeds, combined with greater mobility over wider areas. This standpoint certainly captures the development from first and second generation cellular systems focused on voice support, and the Early short-range wireless data networks, through to today’s 3G cellular and mobile broadband systems; there is every confidence that the trend will continue some way into the future.
上传时间: 2020-05-26
上传用户:shancjb
Wirelessmeshnetworkingisahotandgrowingtopic,stillinitsinfancyin some ways, whilst already shown to be capable in others. From a military beginning, mesh networks moved to civilian use and are now being deployed worldwide as both local area networks (LANs) and metro- politan area networks (MANs). However, these deployments are still ‘leading edge’ and it is not yet clear what the most enduring applications of mesh will be – particularly as the market moves from Early adopters towards widespread take up.
标签: Essentials Networking Wireless Mesh of
上传时间: 2020-05-27
上传用户:shancjb
The wireless market has experienced a phenomenal growth since the first second- generation (2G) digital cellular networks, based on global system for mobile communications (GSM) technology, were introduced in the Early 1990s. Since then, GSM has become the dominant global 2G radio access standard. Almost 80% of today’s new subscriptions take place in one of the more than 460 cellular networks that use GSM technology. This growth has taken place simultaneously with the large experienced expansion of access to the Internet and its related multimedia services.
标签: Performance Evolution GPRS EDGE GSM and
上传时间: 2020-05-27
上传用户:shancjb
In the nineteenth century, scientists, mathematician, engineers and innovators started investigating electromagnetism. The theory that underpins wireless communications was formed by Maxwell. Early demonstrations took place by Hertz, Tesla and others. Marconi demonstrated the first wireless transmission. Since then, the range of applications has expanded at an immense rate, together with the underpinning technology. The rate of development has been incredible and today the level of technical and commercial maturity is very high. This success would not have been possible without understanding radio- wave propagation. This knowledge enables us to design successful systems and networks, together with waveforms, antennal and transceiver architectures. The radio channel is the cornerstone to the operation of any wireless system.
标签: LTE-Advanced Generation Next and
上传时间: 2020-05-27
上传用户:shancjb
Although the origins of radio frequency based wireless networking can be traced back to the University of Hawaii’s ALOHANET research project in the 1970s, the key events that led to wireless networking becoming one of the fastest growing technologies of the Early 21st century have been the ratification of the IEEE 802.11 standard in 1997, and the subsequent development of interoperability certification by the Wi-Fi Alliance (formerly WECA).
标签: Networking Technology Wireless
上传时间: 2020-06-01
上传用户:shancjb
It has been over a decade since the Chinese publication of Line Loss in Electric Power Systems. To keep pace with technological developments, I started a revision as Early as 2002, following the main principles that the theoretical framework and characteristics of the first edition should be retained, with new contents added according to new problems after the reform of electric power systems and the new requirements for line loss management practices and in combination with practical experience.
上传时间: 2020-06-07
上传用户:shancjb
The continuous progress in modern power device technology is increasingly supported by power-specific modeling methodologies and dedicated simulation tools. These enable the detailed analysis of operational principles on the the device and on the system level; in particular, they allow the designer to perform trade- off studies by investigating the operation of competing design variants in a very Early stage of the development process. Furthermore, using predictive computer simulation makes it possible to analyze the device and system behavior not only under regularoperatingconditions, but also at the rim of the safe-operatingarea and beyond of it, where destructive processes occur that limit the lifetime of a power system.
标签: POWERHVMOS_Devices_Compact_Modeli ng
上传时间: 2020-06-07
上传用户:shancjb
adio Frequency Identification (RFID) is a rapidly developing automatic wireless data-collection technology with a long history.The first multi-bit functional passive RFID systems,with a range of several meters, appeared in the Early 1970s, and continued to evolve through the 1980s. Recently, RFID has experienced a tremendous growth,due to developments in integrated circuits and radios, and due to increased interest from the retail industrial and government.
标签: RFID-Enabled Sensors RFID and
上传时间: 2020-06-08
上传用户:shancjb
In the Early days, embedded systems were built primarily by engineers in a pretty exclusive club. Embedded devices and software tools were expensive, and building a functional prototype required significant software engineering and electrical engineering experience.
标签: Arduino Gadgets Make Bots and
上传时间: 2020-06-09
上传用户:shancjb
Design for manufacturability and statistical design encompass a number of activities and areas of study spanning the integrated circuit design and manufacturing worlds. In the Early days of the planar integrated circuit, it was typical for a handful of practitioners working on a particular design to have a fairly complete understanding of the manufacturing process, the resulting semiconductor active and passive devices, as well as the resulting circuit - often composed of as few as tens of devices. With the success of semiconductor scaling, predicted and - to a certain extent even driven - by Moore’s law, and the vastly increased complexity of modern nano-meter scale processes and the billion-device circuits they allow, there came a necessary separation between the various disciplines.
标签: Manufacturability Statistical Design for and
上传时间: 2020-06-10
上传用户:shancjb