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
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In this thesis several asp ects of space-time pro cessing and equalization for wire- less communications are treated. We discuss several di?erent metho ds of improv- ing estimates of space-time channels, such as temp oral parametrization, spatial parametrization, reduced rank channel estimation, b o otstrap channel estimation, and joint estimation of an FIR channel and an AR noise mo del. In wireless commu- nication the signal is often sub ject to intersymb ol interference as well as interfer- ence from other users.
标签: Communications Space-Time Processing Wireless for
上传时间: 2020-06-01
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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
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Each of us is interested in optimization, and telecommunications. Via several meetings, conferences, chats, and other opportunities, we have discovered these joint interests and decided to put together this book.
标签: Telecommunications optimization heuristics
上传时间: 2020-06-01
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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
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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
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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
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In this research, we have designed, developed implemented a wireless sensor networks based smart home for safe, sound and secured living environment for any inhabitant especially elderly living alone. We have explored a methodology for the development of efficient electronic real time data processing system to recognize the behaviour of an elderly person. The ability to determine the wellness of an elderly person living alone in their own home using a robust, flexible and data driven artificially intelligent system has been investigated. A framework integrating temporal and spatial contextual information for determining the wellness of an elderly person has been modelled. A novel behaviour detection process based on the observed sensor data in performing essential daily activities has been designed and developed.
上传时间: 2020-06-06
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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
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It was the publisher’s idea that I write RFID in the Supply Chain: A Guide to Selection and Implementation . Not only am I editor of Enterprise Inte- gration System , Second Edition Handbook and author of The Complete Book of Middleware , I also had some innovative business process and project management ideas on improving the effectiveness of integrating enterprise systems with information on product traceability, the scope of which has been widened by the RFID technology mandates.
标签: Selection Supply Chain Guide RFID the in to
上传时间: 2020-06-08
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