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Discusses the use of a ray-tracing method and the periodic moment method (PMM) for determining wave propagation. How the ray-tracing program is used to find specular and grating ray tubes for each ray tube; Description of the ray-tracing/PMM hybrid approach; Demonstration of results of measurements and simulations for waves propagating in a staircase.

Part II. Discusses the correlation between diversity branches and effective gain to achieve a high diversity effect. Correlation coefficients with regard to whip length, head-to-radio separation and radio inclination angle; Evaluation of diversity gain; Mechanism for obtaining a small correlation coefficient; Experiment in an indoor radio wave propagation environment to verify the results of the correlation coefficient and diversity gain.

Describes radio wave propagation characteristics in tunnel environments. Explanation of the tunnel propagation model and use of geometrical optics theory and uniform theory of diffraction; Validation of tunnel propagation model; Discussion of the results for both line-of-sight (LOS) and non-LOS situations with transmitter outside the tunnel.

Identifies problems with the use of ray-tracing techniques in indoor wave propagation environments. Accuracy of the ray-tracing method for electrically small scatterers; Diffraction modeling for dielectric obstacles; Development of a novel set of diffraction coefficients.

Presents information on a study which described a ray-tracing technique to predict the radio propagation channel parameters for the design of personal communication systems in indoor scenarios. Propagation model; Geometrical model; Use of the angular Z-buffer algorithm.

Discusses a study which described an efficient ray-path search algorithm for radio propagation modeling. Visibility algorithm; Polar sweep algorithm; Extension of the visibility studies to the three-dimensional case; Implementation of a propagation prediction tool.

Presents information on a study which measured the natural propagation of ultrahigh radio frequency waves on an underground train. Measurements used in moving trains; Analysis and results; Conclusion.

Presents information on a study which described a propagation prediction tool developed to facilitate the path loss computation in urban environments. Significance of accurate prediction of signal propagation characteristics in urban mobile radio systems; Mathematical formulation used for the electric field representation; Simulation results and tool validation; Conclusion.

Presents a comprehensive three-dimensional ray-tracing model for interfloor wireless communication systems, and measurements of power delay profiles in a typical two-floor environment. Description of the three dominant propagation paths; Radio frequency measurements; Results and discussions; Conclusion.

Presents a frustum ray tracing technique for the prediction of channel characteristic maps in a complex in-building environment. Limitations of conventional ray tracing methods; Description of the power delay measurement system setup in the target environment; Analysis of results; Conclusion.

Presents information on a study which examined design issues for a microcellular system that can accommodate the heavy traffic load forecast for mature systems. Performance of microcellular systems in residential and commercial environments; Generation of diamond reuse pattern for microcells; Effect of cochannel microcells on microcellular system design; Conclusion.

Presents information on a study which investigated the propagation mechanisms reflection and diffraction of millimeter waves at realistic road surfaces and geometries. Spectacular reflections in mobile-to-mobile scenarios; Obstruction of the line of sight by intermediate vehicles; Diffraction around road crests; Conclusion.

Presents information on a study which described the development and implementation of a propagation model for urban microcells in mobile communication systems. Application scenario of the propagation model; Assessment of the propagation model; Conclusion.

Provides information on a study which proposed a radio propagation hybrid model based on a two-dimensional site-specific model and a statistical model to investigate space diversity in indoor environments. Space diversity performance; Measurement setup and sites and diversity gain; Conclusion.

Provides information on a study which described a three-dimensional (3-D) software suite for urban propagation modeling based on 3-D ray tracing. Implementation of the ray-tracing model; Postprocessing and additions to ray-tracing method; Results and conclusion.

Provides information on a study which proposed two phase models for the wide-band indoor radio propagation channel. Modeling of phase; Comparative evaluations; Simulation algorithms used.

Provides information on a study which proposed a two-dimensional diffraction modeling in the horizontal plane for site-specific propagation prediction in urban microcellular environments. Measurement setup; Comparisons and simulation; Conclusion.

Provides information on a study which proposed a multipath propagation model for line-of-sight street microcells with building roof base sites in urban areas. Measurement of delay profiles; Multipath propagation characteristics for the model; Conclusion.

Investigates the accuracy of a ray-based algorithm versus slope intercept models for propagation prediction in residential environments by comparison with measurements. Background of one concept for personal communication services; Propagation procedure; Measurement sites; Predictions and conclusion.

Presents information on a study which derived protection ratios and field strength levels for orthogonal frequency division multiplex-based digital broadcast systems. Influence of different spatial and temporal probabilities; Three-dimensional wave-propagation model used; Conclusions.

Presents information on a study which proposed a method for the computation of the double knife-edge diffraction in radio-wave propagation. Use of the analytical series calculation for the surface Fresnel integral; Calculation and numerical results; Conclusion.

Presents information on a study of the propagation characteristics at 62 gigahertz of suburban microcellular radios employing omnidirectional receive antennas. Line-of-sight and nonline-of-sight propagation results; Experimental configuration; Discussion and conclusion.

Presents information on a study which resolved the multiple ray paths with frequency dependence for wide-band wireless channel modeling using high-resolution digital processing algorithms. Statistics of multipath propagation; Singular value decomposition and Eigen-matrix pencil method; Numerical results; Conclusions.

Presents information on a study which focused on a channel model for line-of-sight (LOS) street microcells with low-antenna-height base sites. Propagation of radio waves; Evaluation of bit-error rate (BER) performance in LOS street microcells; Conclusions.

Presents information on a study which compared a four-ray model using geometrical theory of diffraction and the Fresnel-Kirchoff scalar approach used in improving propagation of radio waves. Mathematical models; Numerical results and comparison; Conclusions.

Studies the ultra-high frequency (UHF) radio propagation characteristics of straight open-groove structures using the imperfect waveguide method. Formulation; Numerical results and discussion; Conclusions.

Describes the main statistical characteristics of the propagation channel of large transverse dimensions, with the carrier frequency being near 2 GHz. Systems that have to be developed in order to ensure radio coverage of long tunnels; Details on the theoretical and experimental results on the fading distribution.

Presents a study which focused on mobile and personal communications while highlighting radio wave propagation in railway tunnels. Details on empty tunnel radio wave propagation; Characterization of radio wave propagation in loaded train tunnels; Method used to conduct the study; Results of the study.

Highlights a study that developed an empirical model which is used for indoor propagation prediction. Investigation of two approaches for indoor propagation prediction; Background information on the development of the model; Information on the model; Results of the study; Conclusion based on the results.

Presents a method for microcellular communications to predict propagation characteristics. What the model takes into account; Investigation of the propagation loss versus size, number and locations of vehicles and groups of tree on a safe island; Results obtained.

Develops a three-dimensional (3-D) propagation model, combined with a patched-wall model, to predict radio loss in a corridor environment. Utilization of the ray-tracing technique; Comparison of the computed path loss with the measured value of 900-MHz and 2.44-GHz radio propagation; Evidence supporting findings that the fields transmitted through the interior walls give the major contribution to the received field when the radio path lies around a corner.

Investigates the application of diffraction theory and geometrical optics for modeling the propagation in microcellular urban environments. Description of the ray-tracing-based model and measurements; Analysis of the influence of single and double diffraction by building corners; Conclusion that the ray tracing model is appropriate for short propagation prediction and complex environments.

Derives a statistical model for the distribution of rms delay spread (Trms) with a cellular environment. Arguments that Trms should be lognormally distributed at any given distance; What the standard propagation model for cellular communications represents; Correlation between delay spread and shadow fading; Evidence supporting the findings of a compact statistical model for the joint distribution of path gain and delay spread.

Investigates the propagation path loss and multipath fading of experiments of 94-GHz millimeter-wave propagation carried out in indoor channels. Use of an artificial reflector under obstructed (OBS) conditions; Measurement apparatus and experimental procedure; OBS indoor measurements.

Presents techniques for the measurement of local mean signal strength in the context of characterizing the accuracy of propagation prediction models. Methods for measuring local mean signal strength; Effects of antenna rotation on local mean measurements; Linear spatial averaging; Comparison between predicted and measured local average RF power.

Studies pulse propagation characteristics at 2.4 GHz inside buildings. Measurement systems; Impulse response measurement system; Building environments; Power delay profile; Pulse height statistics.

Proposes a deterministic approach to model the radio propagation channels in tunnels with and without traffic. Triangular facets; Vector effective antenna height; Ray tube bounced at a planar interface; Normalized received powers versus distance in a two-parallel coated-plated structure.

Presents corrections to an article about a simulation study for propagation in urban environments.