Conventional approaches to sampling signals or images follow Shannon's theorem: the sampling rate must be at least twice the maximum frequency present in the signal (Nyquist rate). In the field of data conversion, standard analogtodigital…
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Cognitive radio is viewed as a novel approach for improving the utilization of a precious natural resource: the radio electromagnetic spectrum. The cognitive radio, built on a softwaredefined radio, is defined as an intelligent wireless…

In 1960, R.E. Kalman published his famous paper describing a recursive solution to the discretedata linear filtering problem. Since that time, due in large part to advances in digital computing, the Kalman filter has been the subject of extensive…

The recent development of various methods of modulation such as PCM and PPM which exchange bandwidth for signaltonoise ratio has intensified the interest in a general theory of communication. A basis for such a theory is contained in the important…

Today's wireless networks are characterized by a fixed spectrum assignment policy. However, a large portion of the assigned spectrum is used sporadically and geographical variations in the utilization of assigned spectrum ranges from 15% to 85% with…

Choosing good problems is essential for being a good scientist. But what is a good problem, and how do you choose one? The subject is not usually discussed explicitly within our profession. Scientists are expected to be smart enough to figure it out…

We are developing a dual panel breastdedicated PET system using LSO scintillators coupled to position sensitive avalanche photodiodes (PSAPD). The charge output is amplified and read using NOVA RENA3 ASICs. This paper shows that the coincidence…

The spectrum sensing problem has gained new aspects with cognitive radio and opportunistic spectrum access concepts. It is one of the most challenging issues in cognitive radio systems. In this paper, a survey of spectrum sensing methodologies for…

Multiple antennas can be used for increasing the amount of diversity or the number of degrees of freedom in wireless communication systems. We propose the point of view that both types of gains can be simultaneously obtained for a given…

Matrix identities, relations and approximations. A desktop reference for quick overview of mathematics of matrices.

Abstract Increasingly, for many application areas, it is becoming important to include elements of nonlinearity and non Gaussianity in order to model accurately the underlying dynamics of a physical system. Moreover, it is typically crucial to…

This paper considers the model problem of reconstructing an object from incomplete frequency samples. Consider a discretetime signal f∈CN and a randomly chosen set of frequencies Ω. Is it possible to reconstruct f from the partial knowledge of its…

Software radios are emerging as platforms for multiband multimode\npersonal communications systems. Radio etiquette is the set of RF bands,\nair interfaces, protocols, and spatial and temporal patterns that\nmoderate the use of the radio spectrum.…

Following a brief introduction and overview, early chapters cover the basic algebraic relationships of entropy, relative entropy and mutual information, AEP, entropy rates of stochastics processes and data compression, duality of data compression…

A rapid synchronization method is presented for an orthogonal\nfrequencydivision multiplexing (OFDM) system using either a continuous\ntransmission or a burst operation over a frequencyselective channel.\nThe presence of a signal can be detected…

Despite growing evidence that increased brainderived neurotrophic factor (BDNF) and hippocampal adult neurogenesis are necessary for the behavioral actions of antidepressants in rodents, the cellular mechanisms involved in these effects are still…

Suppose x is an unknown vector in Ropfm (a digital image or signal); we plan to measure n general linear functionals of x and then reconstruct. If x is known to be compressible by transform coding with a known transform, and we reconstruct via the…

Orthogonal frequency division multiplexing (OFDM) is a modulation technique which is now used in most new and emerging broadband wired and wireless communication systems because it is an effective solution to intersymbol interference caused by a…

We investigate the use of multiple transmitting and/or receiving antennas for single user communications over the additive Gaussian channel with and without fading. We derive formulas for the capacities and error exponents of such channels, and…

This paper presents an overview of recent progress in the area of multipleinputmultipleoutput (MIMO) spacetime coded wireless systems. After some background on the research leading to the discovery of the enormous potential of MIMO wireless…
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