bluuebunny/crossref_metadata_2025_split huggingface dataset:
Models for MIMO propagation channels: a review
Authors: Yu Kai , Ottersten Björn 
Published: November 2002

AbstractThis paper reviews recently published results on multiple input multiple output (MIMO) channel modeling. Both narrowband and wideband models are considered. We distinguish between two main approaches to MIMO channel modeling, that is, physically based and nonphysically based modeling. The nonphysical models primarily rely on the statistical characteristics of the MIMO channels obtained from the measured data, while the physical models describe the MIMO channel (or its distribution)viasome physical parameters. We briefly review different MIMO channel models and discuss their relationships. Some interesting aspects will be described in more detail and we note areas in which few results are available. Copyright © 2002 John Wiley & Sons, Ltd.
Parallel concatenated turbo multiple antenna coded modulation: principles and performance
Authors: Cui Dongzhe , Haimovich Alexander M. , Chen Hangjun 
Published: November 2002

AbstractA channel‐coding scheme is introduced that features parallel concatenated recursive systematic codes with multilevel modulation and multiple transmit/receive antennas. The proposed scheme is a type of turbo space–time codes and is referred to asturbo multiple antenna coded modulation(turbo‐MACM). Turbo‐MACM combines the advantages of powerful turbo codes with the transmit/receive diversity of multiple antenna coded modulation. The scheme utilizes recursive and systematic constituent codes and features full rate and, as demonstrated by simulations, full spatial diversity. An iterative symbol‐by‐symbolmaximum a posteriori(MAP) algorithm operating in the log domain is developed for decoding turbo‐MACM. Simulation results are provided for 4‐PSK and 8‐PSK schemes over the block‐fading channel. It is shown that the scheme provides an advantage of 3 to 5 dB over conventional space–time codes of comparable complexity. Copyright © 2002 John Wiley & Sons, Ltd.
Channel estimation and interference suppression for space–time coded systems in frequency‐selective fading channels
Authors: Li Ling , Li Hongbin , Yao Yu‐Dong 
Published: November 2002

AbstractIt is of great interest to provide high data rate services in wireless communication systems. In order to support such services, it is desirable to extend space‐time (ST) coding, originally proposed for known, frequency‐nonselective fading channels, to unknown, multipath channels. In this paper, we consider the problem of interference suppression for wireless TDMA (time division multiple access) systems equipped with multiple transmit antennas and receive antennas in frequency‐selective fading channels. A novel scheme with space‐time block coding based transmit diversity (STTD) is presented to estimate the multipath channel, coherently demodulate information symbols, and meanwhile suppress radio interference. The proposed scheme is simple to implement and able to mitigate interference of various origins, including intersymbol interference (ISI), cochannel interference (CCI), and others. Numerical examples are presented to illustrate the performance of the proposed estimator and detector in multipath Rayleigh‐fading channels. Copyright © 2002 John Wiley & Sons, Ltd.
A moment generating function (MGF)‐based approach for performance evaluation of space‐time coded communication systems
Authors: Simon Marvin K. 
Published: November 2002

AbstractA few years back, a generic analysis approach referred to as the MGF method was introduced for the purpose of simplifying the evaluation of the performance of digital communication over fading channels. A particular case of high interest that fell under the umbrella of the methodology was the evaluation of the average error probability performance of systems that employ receive diversity to combat multipath as well as the possible inclusion of error‐correcting coding/decoding for improving power efficiency. In this paper, we extend the methodology to space‐time coded systems. Illustrative examples are explicitly given for space‐time trellis coding. The emphasis of the paper is on the performance analysis tools and their application, as opposed to the design of the space‐time codes themselves. Copyright © 2002 John Wiley & Sons, Ltd.
Space–time receivers for GSM radio interfaces in subway tunnel environments
Authors: González‐López Miguel , Dapena Adriana , Castedo Luis , Lienard Martine , Degauque Pierre , Asarta María J. , Crespo Pedro 
Published: November 2002

AbstractIn this paper, we investigate how to increase the capacity of GSM (Global System for Mobile communications) radio interfaces in subway tunnel environments by means of antenna arrays and Space–Time (ST) receivers. We address the modeling, both theoretically and experimentally, of the multiple‐antenna wireless channels encountered in subway tunnels. We demonstrate that propagation is conveniently modeled by a flat‐fading channel, but there exist strong spatial correlations among channel components that decrease capacity and affect receivers' performance. Different space–time GSM receiving strategies have also been investigated. We first consider ST equalization techniques that only account for the noise and the controlled Intersymbol Interference (ISI) introduced by the modulation format employed in GSM. Then, we analyze the performance of receivers that incorporate ST coding capabilities and show the superior performance of iterative MAP (Maximum a Posteriori) receivers that interchange soft information among the equalizer and the ST decoder. All receivers are evaluated with experimental channels measured in the subway of Paris. Copyright © 2002 John Wiley & Sons, Ltd.
Complex field coded MIMO systems: performance, rate, and trade‐offs
Authors: Ma Xiaoli , Giannakis Georgios B. 
Published: November 2002

AbstractThe quest for reliable high‐rate wireless links motivates fading‐resilient and bandwidth‐efficient communication systems capable of capitalizing on available forms of diversity. This tutorial focuses on linear complex field (LCF) coding—a powerful tool that complements the traditional Galois field (GF) coding, in enabling diversity transmissions over single‐ and multi‐antenna fading channels. Performance and capacity analyses are provided, along with systematic guidelines for constructing LCF encoders, and options available to the designer for selecting LCF decoders. Emphasis is placed on high‐performance and high‐rate designs, and the emerging performance‐rate‐complexity trade‐offs. Copyright © 2002 John Wiley & Sons, Ltd.
Indeterminism and Natural Selection
Authors: Fisher R. A. 
Published: November 2002

The historical origin and the experimental basis of the concept of physical determinism indicate that this basis was removed with the acceptance of the kinetic theory of matter, while its difficulties are increased by the admission that human nature, in its entirety, is a product of natural causation. An indeterministic view of causation has the advantages (a) of unifying the concept of natural law in different spheres of human experience and (b) of a greater generality, which precludes the acceptance of the special case of completely deterministic causation, so long as this is an unproved assumption. It is not inconsistent with the orderliness of the world, or with the fruitful pursuit of natural knowledge. It enriches rather than weakens the concept of of causation. It possesses definite advantages with respect to the one-sidedness of human memory, and to the phenomena of aiming and striving observable in man and other animals. Among biological theories it appears to be most completely in harmony with the theory of natural selection, which in its statistical nature resembles the second law of thermo-dynamics.In an indeterministic world natural causation has a creative element, and science is interested in locating the original causes of effects of special interest, and not merely in pushing a chain of causation backwards ad infinitum. These contrasting tendencies are illustrated by a critique of the mutation theory, and by an attempt more closely to define the sense in which indeterministic causation should be thought of as creative.
Postulational Methods. II
Authors: Kattsoff Louis Osgood 
Published: November 2002

In this study we shall analyze the postulate set into its various elements. In order to carry out our analysis, it is advisable to have before us a typical set.We take the set of five postulates for Boolean Algebras given by H. M. Sheffer in Trans. Am. Math Soc. 14, p. 482 ff.
The Philosophical Significance of the Concept of Probability in Quantum Mechanics
Authors: Northrop F. S. C. 
Published: November 2002

A striking characteristic of contemporary science is its emphasis upon probability. This is especially notable in quantum mechanics.There is a respect in which probability is the same for all scientific theories. Verifiability requires that any theory predict certain numbers which can be compared with the numbers gained by actual operations of measuring. In actual practice these numbers, which we shall term theoretical measurables and operative measurables respectively, never correspond. It becomes necessary, therefore, for the scientist to specify when the deviation between them is such that verification occurs. These specifications are defined by the theory of errors in which the concept of probability has an essential place and a specific meaning. But the theory of errors is the same for all applications; hence, probability as defined by the theory of errors is the same for all scientific theories.
A Critique of Operationalism in Physics
Authors: Lindsay R. B. 
Published: November 2002

It is the aim of this paper to examine certain aspects of a point of view which has attracted much attention in physical methodology. This is the standpoint known as operationalism. We wish to discuss its significance in the construction and interpretation of physical theories.The essential meaning of operationalism in physics is that physical concepts should be defined in terms of actual physical operations. On this view there is no meaning to a concept unless it represents an operation which can be performed in the laboratory. Thus the term “pressure of a gas” signifies nothing until an operation is described which constitutes the measurement of pressure. When one thinks of pressure one must think. of some actual apparatus, such as, for example, some glass and rubber tubing and some mercury and certain operations performed using these until finally one gets a pointer reading which one calls the pressure of the gas. The same stand is taken with respect to length, time, velocity, acceleration, temperature, etc.
The Method of Postulates
Authors: Huntington Edward V. 
Published: November 2002

The subject to which I invite your attention this evening is a very recent development in mathematics which happens to be of great importance to philosophy.The question may perhaps be raised why a terrifying topic like mathematics as introduced into an Institute of Philosophy. There are two answers to this question. In the first place my talk this evening will not be a “mathematical lecture” in any ordinary sense of the term, and no mathematical knowledge whatsoever will be presupposed. In the second place, even if it were to be a mathematical lecture, such an audience as is here assembled tonight would find nothing terrifying in the prospect.
Emergence without Mystery
Authors: Malisoff William Marias 
Published: November 2002

The meaning of emergence has been interpreted in a multitude of ways. What is it that emerges in turn from all this ado about emergence?It is regrettable that the only distinctive overtone that seems to come forth is a lurking sense of mystery or mystification about unexpected or unforseen or “new” forms of organizations. This sense of mystery is conveyed most strongly by those who credit the alleged newness to some sort of subtle influence determined to make new things out of the old. Likewise it is also strongly suggested by those who pretend merely to stumble upon it as an “empirical” find,—but, oh, what a fantastic find!
On Physicalistic Models of Non-Physical Terms
Authors: Bergmann Gustav 
Published: November 2002

Some of the objections most frequently raised against the thesis of physicalism can be summarized as follows:(V) The notions of the biological and social sciences, as e. g. organic whole and Gestalt, means and ends, leadership and hierarchical order, the entire structure and meaning of these scientific systems, are of a type essentially different from those of physics. Consequently they can not be expressed by means of the mathematical language used by physics, and it is “logically impossible” to reduce these sciences to physics.
The Nature of Causation
Authors: Winn Ralph B. 
Published: November 2002

Strange as it may seem, the traditional principle of causality is based on two contradictory assumptions, both of which are generally accepted, explicitly or implicitly, by the contemporary physicists as well as philosophers. That they are not always willing to acknowledge this paradoxical fact, does not save them from the perplexing situation. The two assumptions, in brief, are:(1) That nothing can act at a distance or across an interval of time, without something mediating between the bodies or events; and(2) That every cause precedes its effect and may be located at a distance from it.
The Subject Matter of Psychology
Authors: Bergmann Gustav 
Published: November 2002

The coordination of both logical syntax and methodological analysis of scientific language by scientific empiricism (logical positivism) has achieved a twofold result:1. Elimination of philosophical pseudo-problems and purification of the empirical sciences from the biases engendered in them by these problems.2. Creation of an instrument apt for exact formulation, location, and analysis of the real meaning of the valid philosophical issues.
Diffusion and Biological Membrane Permeability. II
Authors: Reiner John M. 
Published: November 2002

SummaryA kinetic theory of permeability is developed both for the case where the cell membrane is a distinct phase and where it is simply the interface between cell and environment. A general expression for the diffusion current of a substance across the membrane is derived, which depends on two “coefficients of permeability” rather than one. Solubility and adsorption theories of permeability are shown to be special cases of the formulas. The permeability coefficients are expressed in terms of the difference of potential energy of the diffusing substance in the two phases; for a membrane of finite thickness they also involve the thickness, and the diffusion coefficient of the solute in the membrane.
The Meanings of “Meaning”
Authors: Gomperz H. 
Published: November 2002

The following analysis has been undertaken mainly for the purpose of presenting a sample of a method which, as the writer holds, would, if widely and consistently applied, tend considerably to reduce the number and the significance of epistemological problems. The presuppositions characteristic of this method might be summarized in these five statements:
1)You cannot make discoveries by changing the meaning of terms.2)There is wisdom in common sense since it represents the accumulated experience of the race.3)It cannot be impossible to work out common sense into a consistent terminology.4)It is when we lack the patience to do this that epistemological problems seem to arise.5)But when such a terminology is worked out, it will prove rather disappointing since it will just express, in a somewhat clarified form, what all the world has always been aware of.
Class and Number
Authors: Ushenko A. P. 
Published: November 2002

To bring clearly before the mind what is meant by class and to distinguish this notion from all the notions to which it is allied, is one of the most difficult and important problems of mathematical philosophy.”When Russell wrote this in 1903, he could illustrate the difficulty of the problem by his own confusing attempt at a solution. He was able to demonstrate the importance of classes for mathematical philosophy in his later work: the definition of cardinal number as a class of classes similar to a given class served him as a cornerstone for the derivation of mathematics from logic.
The Microcoulomb Experiment
Authors: Ehrenhaft Felix 
Published: November 2002

SummaryThe present paper deals with the determination of the size and charge of a single submicroscopic particle, measured in a small horizontal condenser of a diameter of approximately 8 mm., using the author's method first stated April 1910. To obtain the highest sensitivity, author used solid particles (spheres) of an order of magnitude under 3 × 10–5 cm. and found charges less than that of the electron. Various objections were raised against his findings, namely that the particles investigated were not spheres, and that their density was not that of the macroscopic substance, so that his findings of charges less than the electronic charge were merely imaginary. The author has succeeded in precipitating and measuring a particle after having observed it in the condenser under normal and also very high gas pressures. The particles were shown to be perfect spheres. A new method is indicated whereby it is possible to determine the size of sub-microscopic spheres by pushing together two equal spheres with a micromanipulator; the two diffraction disks overlap and render it very easy to determine the actual size. It is also possible to show that the density of each individual sphere is that of the macroscopic substance, since it can be computed easily from the velocity of fall at high gas pressures (according to Stokes' law). These two data being accurately determined, the author still found charges considerably less than the electronic charge, and the deviations are too great to be accounted for by errors of observation. The reason that the author has used a solid substance (red amorphous Se) and not oil, which is a liquid, was in the first place, that liquids evaporate, and therefore do not yield correct results, and secondly, because liquid spheres are not certain to preserve their sphericity when precipitated. Thus charges less than that of the electron are to be considered as actually existing.
Umbrellaology, or, Methodology in Social Science
Authors: Somerville John 
Published: November 2002

Let us invoke philosophic license for a moment to suppose you receive the following letter:“Dear Sir:I am taking the liberty of calling upon you to be the judge in a dispute between me and an acquaintance who is no longer a friend. The question at issue is this: Is my creation, umbrellaology, a science? Allow me to explain this situation. For the past eighteen years, assisted by a few faithful disciples, I have been collecting materials on a subject hitherto almost wholly neglected by scientists, the umbrella. The results of my investigations to date are embodied in the nine volumes which I am sending to you under separate cover. Pending their receipt, let me describe to you briefly the nature of their contents and the method I pursued in compiling them. I began on the Island of Manhattan. Proceeding block by block, house by house, family by family and individual by individual I ascertained 1) the number of umbrellas possessed, 2) their size, 3) their weight, 4) their color. Having covered Manhattan after many years, I eventually extended the survey to the other boroughs of the City of New York, and at length completed the entire city. Thus I was ready to carry forward the work to the rest of the state and indeed the rest of the United States and the whole known world.
The Limits of Freedom in Philosophy
Authors: Miller Cecil H. 
Published: November 2002

This paper is a study in restraint on freedom of speculation. In view of the subtlety of the subject it has seemed advisable to begin the report with a list of the presuppositions initiating and determining the study. These are as follows:1). That freedom of speculation is a prerequisite to sound mental health, in individuals as well as in large-scale social units.2). That, consequently, individual and institutional faculties are alike deficient if and insofar as they prevent or abridge such freedom.3). That the same factors operating in one aspect to restrain the influence of promulgated theories operate in another aspect to inhibit the free conception and hamper the expression of speculation not so promulgated.4). That as it is the purpose of individual philosophizing to surround with coherent speculation or theory subjects of primarily individual interest, it is the purpose of institutional philosophizing similarly to invest with theory subjects of common social interest.5). That speculation in general, whether individual or institutional, is free when the prevalent tendency is for subjects of comparable interest to be accorded comparable quantities of speculation; and that when and insofar as this tendency does not prevail speculation is to that extent not free but restrained.
Logical Systems and the Principles of Logic
Authors: Farber Marvin 
Published: November 2002

Doubts concerning the validity of logic are as old as the empirical criticism of science. In the last two decades the idea that truth is relative to given sets of basic assumptions has been prominent; and the controversy about the principle of excluded middle has focussed renewed attention upon the nature of logic and its fundamental principles.Recent investigations in formal logic have contributed greatly to the understanding of the principles of logic. It is simply a misunderstanding to conclude from them that the logical principles have been suspended, despite the various formal structures which are called “logics.” The purely formal treatment of problems concerning the foundations of logic, while necessarily undertaken as far as it can go, has essential limitations.
The Purpose of Purpose
Authors: Weiss Paul 
Published: November 2002

Most of man's organs can be utilized in more than one way. His hands can be used to grip and to push, his throat can serve to swallow and to expel, he uses his tongue to taste and to talk, his nose to breathe and to smell.If each mode of activity required the use of a different organ, a man would have to be much more cumbersome than he now is, or he would have to give up doing some of the things of which he is now capable. He would need at least a score of hands if he needed one with which to grasp, another with which to lift, a third with which to push, a fourth with which to twist etc. Because he has only two, capable of doing twenty different things, he is much more compact and flexible than he otherwise would be.
Prime Number and Cosmical Number
Authors: Hartman Robert S. 
Published: November 2002

The conformity of mathematics and physics has so far been taken for granted. Philosophical explanations of that fundamental fact have never been satisfactory, mathematical explanations never had been attempted. In the following a fundamental theorem for the conformity of mathematics and physics will be demonstrated.Mathematics can be defined as the science of Number, physics as the science of Matter. The elementary constituents of mathematics are the prime numbers, those of matter the particles, particularly protons and electrons. The only essential property of these elements as such is their existence, given within a given complex or space. Their fundamental relation is their distribution within their respective spaces. The theorem of the distribution of primes in the arithmetical series of numbers is the fundamental theorem of mathematics. The fundamental theorem of physics would be a theorem of the distribution of particles in geometrical space. If it were shown that both theorems were equal, the essential conformity of mathematics and physics would be mathematically demonstrated.