An accurate UTD extension to a ray-launching algorithm for the analysis of complex indoor radio environments

This paper deals with the efficient combination of two well-established electromagnetic methods, a shooting and bouncing Rays (SBR) algorithm on the basis of geometrical optics (GO) and diffraction calculation on the basis of the uniform theory of diffraction (UTD). While the conventional GO method is able to accurately calculate field contributions due to reflection and refraction, the further propagation of diffracted rays is generally not considered in SBR approaches. Thus, the aim of this work is to describe the implementation of diffracted rays according to the UTD concept into an SBR code. A convergence analysis to obtain the optimal calculation parameters for the diffracted rays is presented. This novel implementation with the optimal parameters allows modeling the radio wave propagation channel in complex indoor environments with a large number of obstacles. The comparison with real measurements proves that the proposed hybrid GO–UTD algorithm yields excellent results and that the UTD extension definitely improves the simulations of the ray-launching algorithm for realistic environments.

[1]  R. Kouyoumjian,et al.  A uniform geometrical theory of diffraction for an edge in a perfectly conducting surface , 1974 .

[2]  Soon Yim Tan,et al.  A microcellular communications propagation model based on the uniform theory of diffraction and multiple image theory , 1996 .

[3]  H. Hashemi,et al.  The indoor radio propagation channel , 1993, Proc. IEEE.

[4]  Theodore S. Rappaport,et al.  Site-specific propagation prediction for wireless in-building personal communication system design , 1994 .

[5]  J. Keller,et al.  Geometrical theory of diffraction. , 1962, Journal of the Optical Society of America.

[6]  M. Hata,et al.  Empirical formula for propagation loss in land mobile radio services , 1980, IEEE Transactions on Vehicular Technology.

[7]  P. Constantinou,et al.  A UTD propagation model in urban microcellular environments , 1997 .

[8]  P. Bernardi,et al.  An accurate UTD model for the analysis of complex indoor radio environments in microwave WLAN systems , 2004, IEEE Transactions on Antennas and Propagation.

[9]  Gianluca Gennarelli,et al.  A Uapo-Based Model for Propagation Prediction in Microcellular Environments , 2009 .

[10]  Chang-Fa Yang,et al.  A ray tracing method for modeling indoor wave propagation and penetration , 1996, IEEE Antennas and Propagation Society International Symposium. 1996 Digest.

[11]  Henry L. Bertoni,et al.  Mechanisms governing UHF propagation on single floors in modern office buildings , 1992 .

[12]  F. Weinmann,et al.  UTD Shooting-and-Bouncing Extension to a PO / PTD Ray Tracing Algorithm , 2009 .

[13]  J. Tarng,et al.  Three-dimensional modeling of 900-MHz and 2.44-GHz radio propagation in corridors , 1997 .

[14]  David J. Y. Lee,et al.  Propagation prediction in and through buildings , 2000, IEEE Trans. Veh. Technol..

[15]  Hristo D. Hristov,et al.  Fresnal Zones in Wireless Links, Zone Plate Lenses and Antennas , 2000 .

[16]  R. Luebbers.  A heuristic UTD slope diffraction coefficient for rough lossy wedges , 1989 .

[17]  Noh-Hoon Myung,et al.  A deterministic ray tube method for microcellular wave propagation prediction model , 1999 .

[18]  Francisco Falcone,et al.  Convergence Analysis in Deterministic 3D Ray Launching Radio Channel Estimation in Complex Environments , 2014 .

[19]  C. Balanis.  Advanced Engineering Electromagnetics , 1989 .

[20]  F. Weinmann,et al.  Ray tracing with PO/PTD for RCS modeling of large complex objects , 2006, IEEE Transactions on Antennas and Propagation.

[21]  G. Deschamps,et al.  A uniform asymptotic theory of electromagnetic diffraction by a curved wedge , 1976 .

[22]  Francisco Falcone,et al.  A Ray Launching-Neural Network Approach for Radio Wave Propagation Analysis in Complex Indoor Environments , 2014, IEEE Transactions on Antennas and Propagation.

[23]  R.J. Luebbers,et al.  Comparison of GTD and FDTD predictions for UHF radio wave propagation in a simple outdoor urban environment , 1997, IEEE Antennas and Propagation Society International Symposium 1997. Digest.

[24]  S. Yoshida,et al.  Propagation factors controlling mean field strength on urban streets , 1984 .

[25]  Shyh-Kang Jeng,et al.  An SBR/image approach for radio wave propagation in indoor environments with metallic furniture , 1997 .