It is commonly accepted today that optical fiber communications have revolutionized telecommunications. Indeed, dramatic changes have been induced in the way we interact with our relatives, friends, and colleagues: we retrieve information, we entertain and educate ourselves, we buy and sell, we organize our activities, and so on, in a long list of activities. Optical fiber systems initially allowed for a significant curb in the cost of transmission and later on they sparked the PROCESS of a major rethinking regarding some, generation-old, telecommunication concepts like the (OSI)-layer definition, the lack of cross-layer dependency, the oversegmentation and overfragmentation of telecommunica- tions networks, and so on.
上传时间： 2020-05-27
上传用户：shancjb
This research work aims at eliminating the off-chip RF SAW filters from fre- quency division duplexed (FDD) receivers. In the first approach, a monolithic passive RF filter was constructed using on-chip capacitors and bondwire inductors. The bond- wire characteristics were studied in details and the effect of mutual inductive coupling between the bondwires on the filter performance was analyzed. Based on that, a bond- wire configuration was proposed to improve the frequency response of the filter. The filter was implemented in 0.18 µm CMOS PROCESS for WCDMA applications.
标签： Interference Mitigation Techniques
上传时间： 2020-05-27
上传用户：shancjb
With the rapid expansion of wireless consumer products,there has been a con- siderable increase in the need for radio-frequency (RF) planning, link plan- ning, and propagation modeling.A network designer with no RF background may find himself/herself designing a wireless network. A wide array of RF planning software packages can provide some support, but there is no substi- tute for a fundamental understanding of the propagation PROCESS and the lim- itations of the models employed. Blind use of computer-aided design (CAD) programs with no understanding of the physical fundamentals underlying the PROCESS can be a recipe for disaster. Having witnessed the results of this approach, I hope to spare others this frustration.
标签： Introduction Propagation to RF
上传时间： 2020-05-27
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Before delving into the details of orthogonal frequency division multiplexing (OFDM), relevant background material must be presented first. The purpose of this chapter is to provide the necessary building blocks for the development of OFDM principles. Included in this chapter are reviews of stochastic and random PROCESS, discrete-time signals and systems, and the Discrete Fourier Transform (DFT). Tooled with the necessary mathematical foundation, we proceed with an overview of digital communication systems and OFDM communication systems. We conclude the chapter with summaries of the OFDM wireless LAN standards currently in existence and a high-level comparison of single carrier systems versus OFDM.
上传时间： 2020-05-31
上传用户：shancjb
With the advent of IMT-2000, CDMA has emerged at the focal point of interest in wireless communications. Now it has become impossible to discuss wireless communications without knowing the CDMA technologies. There are a number of books readily published on the CDMA technologies, but they are mostly dealing with the traditional spread-spectrum technologies and the IS-95 based CDMA systems. As a large number of novel and interesting technologies have been newly developed throughout the IMT-2000 standardization PROCESS in very recent years, new reference books are now demanding that address the diverse spectrum of the new CDMA technologies.
标签： Communications Scrambling Techniques CDMA for
上传时间： 2020-06-01
上传用户：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.
标签： Telecommunications PROCESSing Signal for
上传时间： 2020-06-01
上传用户：shancjb
Part I provides a compact survey on classical stochastic geometry models. The basic models defined in this part will be used and extended throughout the whole monograph, and in particular to SINR based models. Note however that these classical stochastic models can be used in a variety of contexts which go far beyond the modeling of wireless networks. Chapter 1 reviews the definition and basic properties of Poisson point PROCESSes in Euclidean space. We review key operations on Poisson point PROCESSes (thinning, superposition, displacement) as well as key formulas like Campbell’s formula. Chapter 2 is focused on properties of the spatial shot-noise PROCESS: its continuity properties, its Laplace transform, its moments etc. Both additive and max shot-noise PROCESSes are studied. Chapter 3 bears on coverage PROCESSes, and in particular on the Boolean model. Its basic coverage characteristics are reviewed. We also give a brief account of its percolation properties. Chapter 4 studies random tessellations; the main focus is on Poisson–Voronoi tessellations and cells. We also discuss various random objects associated with bivariate point PROCESSes such as the set of points of the first point PROCESS that fall in a Voronoi cell w.r.t. the second point PROCESS.
标签： Stochastic Geometry Networks Wireless Volume and
上传时间： 2020-06-01
上传用户：shancjb
Electrostatic discharge (ESD) is one of the most prevalent threats to the reliability of electronic components. It is an event in which a finite amount of charge is trans- ferred from one object (i.e., human body) to another (i.e., microchip). This PROCESS can result in a very high current passing through the microchip within a very short period of time, and, hence, more than 35% of chip damages can be attributed to an ESD-related event. As such, designing on-chip ESD structures to protect integrated circuits against the ESD stresses is a high priority in the semiconductor industry.
标签： Electrostatic Protection Discharge
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 planarization technology of Chemical-Mechanical-Polishing (CMP), used for the manufacturing of multi- level metal interconnects for high-density Integrated Circuits (IC), is also readily adaptable as an enabling technology in MicroElectroMechanical Systems (MEMS) fabrication, particularly polysilicon surface micromachining. CMP not only eases the design and manufacturability of MEMS devices by eliminating several photolithographic and film issues generated by severe topography, but also enables far greater flexibility with PROCESS complexity and associated designs. T
标签： mechanical polishing Chemical
上传时间： 2020-06-06
上传用户：shancjb
