Commoditization is a serious threat to the telecommunications industry. Most CSPs offer similar services at rates designed to win what has become a price war. As a result, many face decreasing margins and difficulty sustaining differentiation based on prices or products alone. On top of commoditization, CSPs also face competition from OTT providers and an increasingly knowledgeable and demanding customer base. With access to growing amounts of data from an ever-increasing number of sources and devices, today’s empowered, savvy consumers know what they want and expect to get it.
標簽： RestoringConnections_IBM_CPL
上傳時間： 2020-06-01
上傳用戶：shancjb
Driven by the desire to boost the quality of service of wireless systems closer to that afforded by wireline systems, space-time processing for multiple-input multiple-output (MIMO) wireless communications research has drawn remarkable interest in recent years. Excit- ing theoretical advances, complemented by rapid transition of research results to industry products and services, have created a vibrant and growing area that is already established by all counts. This offers a good opportunity to reflect on key developments in the area during the past decade and also outline emerging trends.
標簽： Space-Time Processing
上傳時間： 2020-06-01
上傳用戶：shancjb
Radio frequency spectrum is a scarce and critical natural resource that is utilized for many services including surveillance, navigation, communication, and broadcast- ing. Recent years have seen tremendous growth in the use of spectrum especially by commercial cellular operators. Ubiquitous use of smartphones and tablets is one of the reasons behind an all-time high utilization of spectrum. As a result, cellular operators are experiencing a shortage of radio spectrum to meet bandwidth demands of users. On the other hand, spectrum measurements have shown that much spectrum not held by cellular operators is underutilized even in dense urban areas. This has motivated shared access to spectrum by secondary systems with no or minimal impact on incumbent systems. Spectrum sharing is a promising approach to solve the problem of spectrum congestion as it allows cellular operators access to more spectrum in order to satisfy the ever-growing bandwidth demands of commercial users.
標簽： Spectrum Sharing Between Radars
上傳時間： 2020-06-01
上傳用戶：shancjb
The first edition of this book was published in 1992. Nine years later it had become clear that a second edition was required because of the rapidly changing nature of telecommunication. In 1992, the Internet was in existence but it was not the household word that it is in the year 2001. Cellular telephones were also in use but they had not yet achieved the popularity that they enjoy today. In the current edition, Chapter 1 has been revised to include a section on the Internet. Chapter 10 is new and it covers the facsimile machine; I had overlooked this important tele- communication device in the first edition. Chapter 11 is also new and it describes the pager, the cordless telephone and the cellular telephone system. These are examples of a growing trend in telecommunications to go ‘‘wireless’’.
標簽： Telecommunication Circuit Design 2nd
上傳時間： 2020-06-01
上傳用戶：shancjb
The information age is exploding around us, giving us access to dizzying amounts of data the instant it becomes available. Smart phones and tablets provide an untethered experience that offers stream- ing video, audio, and other media formats to just about any place on the planet. Even people who are not “computer literate” use Facebook to catch up with friends and family, use Google to research a new restaurant choice and print directions to get there, or Tweet their reactions once they have sampled the fare. The budding Internet-of-things will only catalyze this data eruption. The infrastructure supporting these services is also growing exponentially, and the technology that facilitates this rapid growth is virtualization.
上傳時間： 2020-06-01
上傳用戶：shancjb
Notwithstanding its infancy, wireless mesh networking (WMN) is a hot and growing field. Wireless mesh networks began in the military, but have since become of great interest for commercial use in the last decade, both in local area networks and metropolitan area networks. The attractiveness of mesh networks comes from their ability to interconnect either mobile or fixed devices with radio interfaces, to share information dynamically, or simply to extend range through multi-hopping.
標簽： Multi-hop Networks WiMAX WiFi Mesh LTE and
上傳時間： 2020-06-01
上傳用戶：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).
標簽： Networking Technology Wireless
上傳時間： 2020-06-01
上傳用戶：shancjb
The phenomenon of electrostatic discharge (ESD) has been known for a long time, but recently a growing interest has been observed in ESD in radio frequency (RF) technology and ESD issues in RF applications.
標簽： Technology Circuits ESD and RF
上傳時間： 2020-06-05
上傳用戶：shancjb
As we enter the next millennium, there are clear technological patterns. First, the electronic industry continues to scale microelectronic structures to achieve faster devices, new devices, or more per unit area. Secondly, electrostatic charge, electrostatic discharge (ESD), electrical overstress (EOS) and electromagnetic emissions (EMI) continue to be a threat to these scaled structures. This dichotomy presents a dilemma for the scaling of semiconductor technologies and a future threat to new technologies. Technological advancements, material changes, design techniques, and simulation can fend off this growing concern – but to maintain this ever-threatening challenge, one must continue to establish research and education in this issue.
標簽： ESD-Phenomena-and-the-Reliability
上傳時間： 2020-06-05
上傳用戶：shancjb
The solid high-polymer-film-type fuel cell (PEM-FC) system is used as the power supply equipment for transportation and replaces an internal combustion engine. A reduction of the environmental load is expected through the cogeneration system’s (CGS) use of the PEM-FC system as a distributed power supply to individual houses, apartments, and so forth [1–3]. The growing use of distributed power systems, such as fuel cells, the reduction of power-transmission losses, and an increase of waste heat recovery are expected. Therefore, the reduction of carbon- dioxide emission is also expected as compared to conventional energy supply methods using commercial electric power.
標簽： Micro-grids Fuel Cell
上傳時間： 2020-06-07
上傳用戶：shancjb
