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.
标签: Spectrum Sharing Between Radars
上传时间: 2020-06-01
上传用户:shancjb
The serious study of the practice of how to determine the appropriate content of a specification is a seldom-appreciated pastime. Those who have the responsibility to design a product would prefer a greater degree of freedom than permitted by the con- tent of a specification. Many of those who would manage those who would design a product would prefer to allocate all of the project funding and schedule to what they consider more productive labor. These are the attitudes, of course, that doom a project to defeat but they are hard to counter No matter how many times repeated by design engineers and managers. A system engineer who has survived a few of these experiences over a long career may retire and forget the past but we have an endur- ing obligation to work toward changing these attitudes while trying to offer younger system engineers a pathway toward a more sure success in requirements analysis and specification publishing.
标签: Requirements Analysis System
上传时间: 2020-06-01
上传用户:shancjb
Welcome to the world of wireless communications and the logical extension to the broadband architectures that are emerging as the future of the industry. No aspect of communications will be untouched by the wireless interfaces;No part of our working environment will be left untouched either. As the world changes and the newer techNologies emerge, we can expect to see more in the line of untethered communications than in the wired inter- faces.
标签: Broadband Wireless Handbook
上传时间: 2020-06-01
上传用户:shancjb
A wireless ad-hoc network is a wireless network deployed without any infrastructure. In such a network, there is No access point or wireless router to forward messages among the computing devices. Instead, these devices depend on the ad-hoc mode of their wireless net‐ work interface cards to communicate with each other. If the Nodes are within the transmis‐ sion range of the wireless signal, they can send messages to each other directly. Otherwise, the Nodes in between will forward the messages for them. Thus, each Node is both an end system and a router simultaneously.
上传时间: 2020-06-01
上传用户:shancjb
This effort started as an answer to the numerous questions the authors have repeatedly had to answer about electrostatic discharge (ESD) protection and input/output (1/0) designs. In the past No comprehensive book existed suffi- ciently covering these areas, and these topics were rarely taught in engineering schools. Thus first-time I/O and ESD protection designers have had consider- able trouble getting started. This book is in part an answer to such needs.
上传时间: 2020-06-05
上传用户:shancjb
Failure analysis is invaluable in the learning process of electrostatic discharge (ESD) and electrical overstress (EOS) protection design and development [1–8]. In the failure analysis of EOS, ESD, and latchup events, there are a number of unique failure analysis processes andinformationthatcanprovidesignificantunderstandingandillumination[4].Today,thereis still No design methodology or computer-aided design (CAD) tool which will predict EOS, ESDprotectionlevels,andlatchupinasemiconductorchip;thisisoneofthesignificantreasons why failure analysis is critical to the ESD design discipline.
标签: Mechanisms Failure Models ESD and
上传时间: 2020-06-05
上传用户:shancjb
The goal of this book is to introduce the simulation methods necessary to describe the behaviour of semiconductor devices during an electrostatic discharge (ESD). The challenge of this task is the correct description of semiconductor devices under very high current density and high temperature transients. As it stands, the book can be No more than a snapshot and a summary of the research in this field during the past few years. The authors hope that the book will provide the basis for further development of simulation methods at this current frontier of device physics.
标签: Development Protection ESD
上传时间: 2020-06-05
上传用户:shancjb
It has been said that the move from narrowband to broadband access is the second revolution for the Internet — ‘broadband is more bandwidth than you can use’. Once users have experienced broadband access there is No turning back. A whole new world of applications and services becomes possible. No longer is it the ‘world- wide wait’. The speed of response and visual quality enabled by broadband finally allows the Internet to reach its true potential.
上传时间: 2020-06-06
上传用户:shancjb
In the present era, low observability is one of the critical requirements in aerospace sector, especially related to defense. The stealth techNology essentially relates to shaping and usage of radar absorbing materials (RAM) or radar absorbing struc- tures (RAS). The performance of such radar cross section (RCS) reduction tech- niques is limited by the bandwidth constraints, payload requirements, and other structural issues. Moreover, with advancement of materials science, the structure geometry No longer remains key decisive factor toward stealth.
标签: Fundamentals Design Radar of EM
上传时间: 2020-06-06
上传用户:shancjb
With the continued growth in the world's population, there is a need to ensure availability of eNough food to feed everyone. Advances in science and techNology have helped Not only to increase food production, but also to reduce food wastage. However, the latter has the potential to be improved to a significant extent through appropriate matching of supply and demand, and with proper handling during storage and transit. Given the amount of food wastage that occurs after a food item leaves the “farm” on its way to the “fork,” and the availability of means to reduce such wastage, there really is No excuse for feigned igNorance.
标签: Automation Industry Network Sensor RFID Food and the in
上传时间: 2020-06-08
上传用户:shancjb