This book was born from the perception that there is much more to spectrum use and sharing than one sees reflected in publications, whether academic, commercial or political. the former – in good research style – tend towards reductionism and concentrate on specific, detailed aspects. commercial publications tend to empha- size the positive aspects and they tend to put promise above practice. Given the ever increasing pace of technology development and recent successes of new wireless technologies, some pundits predict large-scale spectrum scarcity, potentially lead- ing to economic catastrophe. Although economic theory has a hard time explaining recent events that shook the world economy, the notion of spectrum scarcity is intui- tively acceptable, even if not correct or immediately relevant.
上傳時間: 2020-06-01
上傳用戶:shancjb
Ultra-wideband (UWB) technology enables high data-rate short-range communica- tion, in excess of hundredmegabit-per-secondsand up to multi-gigabit-per-seconds, over a wide spectrum of frequencies, while keeping power consumption at low lev- els. This low power operation results in a less-interfering co-existence with other existed communication technologies (e.g., UNII bands). In addition to carrying a huge amount of data over a distance of up to 230 feet at very low power (less than 0.5mW), the UWB signal has the ability to penetrate through the doors and other obstacles that tend to reflect signals at more limited bandwidths and higher power densities.
標簽: Silicon-Based Front-Ends RF
上傳時間: 2020-06-01
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An acronym for Multiple-In, Multiple-Out, MIMO communication sends the same data as several signals simultaneously through multiple antennas, while still utilizing a single radio channel. This is a form of antenna diversity, which uses multiple antennas to improve signal quality and strength of an RF link. The data is split into multiple data streams at the transmission point and recombined on the receive side by another MIMO radio configured with the same number of antennas. The receiver is designed to take into account the slight time difference between receptions of each signal, any additional noise or interference, and even lost signals.
標簽: Understanding_the_Basics_of_MIMO
上傳時間: 2020-06-01
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Visible light communications (VLC) is the name given to an optical wireless communication system that carries information by modulating light in the visible spectrum (400–700 nm) that is principally used for illumination [1–3]. The communications signal is encoded on top of the illumination light. Interest in VLC has grown rapidly with the growth of high power light emitting diodes (LEDs) in the visible spectrum. The motivation to use the illumination light for communication is to save energy by exploiting the illumination to carry information and, at the same time, to use technology that is “green” in comparison to radio frequency (RF) technology, while using the existing infrastructure of the lighting system.
標簽: Communication Visible Light
上傳時間: 2020-06-01
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This book is concerned with integrated circuits and systems for wireless and mobile communications. Circuit techniques and implementation of reconfigurable low-voltage and low-power single-chip CMOS transceivers for multiband and multi- mode universal wireless communications are the focus of the book. Applications encompass both long-range mobile cellular communications (GSM and UMTS) and short-range wireless LANs (IEEE802.11 and Bluetooth). Recent advances in research into transceiver architecture, RF frontend, analogue baseband, RF CAD and automatic testing are reported.
標簽: Communication Wireless Circuits Systems and
上傳時間: 2020-06-01
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This paper reviews key factors to practical ESD protection design for RF and analog/mixed-signal (AMS) ICs, including general challenges emerging, ESD-RFIC interactions, RF ESD design optimization and prediction, RF ESD design characterization, ESD-RFIC co-design technique, etc. Practical design examples are discussed. It means to provide a systematic and practical design flow for whole-chip ESD protection design optimization and prediction for RF/AMS ICs to ensure 1 st Si design success.
標簽: ESD_protection_for_RF_and_AMS_ICs
上傳時間: 2020-06-05
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Micro-Electro-Mechanical Systems (MEMS) are miniature systems composed ofintegratedelectricalandmechanicalpartstosenseand/orcontrolthingsonaμmscale. The concept of MEMS is attributed to Richard Feynman’s famous talk on December 29th, 1959 [2,3]. Dr. Feynman foresaw many aspects of future MEMS development with his insight in microphysics. In particular, material properties in the μm scale are differentfrombulkpropertiesandthescalingdownofintegratedcircuits(IC)fabrication technology has been a major driving force of MEMS development.
標簽: Performance High MEMS RF
上傳時間: 2020-06-06
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Over many years, RF-MEMS have been a hot topic in research at the technology and device level. In particular, various kinds of mechanical Si-MEMS resonators and piezoelectric BAW (bulk acoustic wave) resonators have been developed. The BAW technology has made its way to commercial products for passive RF filters, in particular for duplexers in RF transceiver front ends for cellular communica- tions. Beyond their use in filters, micromachined resonators can also be used in conjunction with active devices in innovative circuits and architectures.
標簽: MEMS-based Circuits Systems and
上傳時間: 2020-06-06
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GaN is an already well implanted semiconductor technology, widely diffused in the LED optoelectronics industry. For about 10 years, GaN devices have also been developed for RF wireless applications where they can replace Silicon transistors in some selected systems. That incursion in the RF field has open the door to the power switching capability in the lower frequency range and thus to the power electronic applications. Compared to Silicon, GaN exhibits largely better figures for most of the key specifications: Electric field, energy gap, electron mobility and melting point. Intrinsically, GaN could offer better performance than Silicon in terms of: breakdown voltage, switching frequency and Overall systems efficiency.
標簽: GaN-on-Si Displace and SiC Si
上傳時間: 2020-06-07
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To a quantum mechanic the whole universe is one godawful big interacting wavefunction ? but to the rest of us, it’s a world full of separate and distinguishable objects that hurt us when we kick them. At a few months of age, human children recognize objects, expect them to be permanent and move continuously, and display surprise when they aren’t or don’t. We associate visual, tactile, and in some cases audible and olfactory sensations with identifiable physical things. We’re hardwired to understand our environment as being composed of separable things with specific properties and locations. We understand the world in terms of what was where when.
上傳時間: 2020-06-08
上傳用戶:shancjb