IST-1999-11729 METRA D 2 MIMO Channel Characterisation Contractual Date of Delivery to the CEC : 31 December 2000 Actual Date of Delivery to the CEC : 7

This document presents the outcomes of the modelling activities of multiple-input multipleoutput (MIMO) radio channels performed within the METRA project. A stochastic model of MIMO radio channels is proposed, and its implementation in COSSAP is described. Guidelines for choosing the input parameters of the model are also given. On the other hand, an experimental set-up for sounding MIMO channels is presented, as well as the environments in which it has been deployed during measurement campaigns. Finally, the results from the measurements are compared to those produced by the COSSAP model as a mean of validating the proposed stochastic model. Keyword list: MIMO channel, space-domain modelling, azimuth dispersion, channel sounder IST-1999-11729 METRA Doc. : IST-1999-11729/AAU-WP2-D2-V1.1. doc Title: MIMO Channel Characterisation 8 February, 2001 File: AAU-WP2-D2-V1.1. doc Page 2 of 57 0 EXECUTIVE SUMMARY This document presents the outcome of the modelling activities of multiple-input multipleoutput (MIMO) radio channels performed in the framework of the METRA project. The scope of this project is to study MIMO antenna concepts for the 3 generation mobile communication systems, namely Universal Mobile Telecommunication Services (UMTS). These modelling activities have combined two approaches, simulations and experiments. To enable METRA partners and other research teams outside of the METRA consortium to investigate the potentialities of MIMO radio channels, a stochastic model has been proposed. Its major strength lies in the fact that it collapses all the correlation information about the environment under study, usually extracted from the geometrical characteristics of the set-up, in two correlation matrices, which are measured at the terminations of the link. The timedomain characterisation of the set-up is conventionally defined with Power Delay Spectrum (PDS) and Doppler spectrum. Additionally, a review of the open literature has been made, to guide the choice of input parameters and spectra of the proposed model according to the considered environment. Moreover, this stochastic model has been implemented into a COSSAP primitive block. COSSAP is a widely used simulation tool. Regarding the experimental approach, a MIMO channel sounder has been built on the basis of the Technology in Smart antennas for Universal Advanced Mobile Infrastructure (TSUNAMI) II testbed. The most innovative contribution in that respect has been the design, the building and the operation of a trolley carrying a slide allowing to perform measurement runs of more than 10 wavelengths with smart antenna set-ups. This enables to perform a thorough characterisation of MIMO channels in both spaceand time-domain. A total of 99 positions related to 6 different environments have been investigated with the channel sounder. For each of these positions, the typical parameters to be used as inputs of the proposed stochastic model have been derived, and simulations have been performed. Measurement and simulation results have then been compared through the eigenanalysis of the recorded and synthesised MIMO channel impulse responses (IR). It is shown that the agreement between them is fairly good, which enables to conclude the validity of the model. 1 The terminology “Power Delay Spectrum” is adopted from [Proakis95, p. 762]. IST-1999-11729 METRA Doc. : IST-1999-11729/AAU-WP2-D2-V1.1. doc Title: MIMO Channel Characterisation 8 February, 2001 File: AAU-WP2-D2-V1.1. doc Page 3 of 57 DISCLAIMER The work associated with this report has been carried out in accordance with the highest technical standards and the METRA partners have endeavoured to achieve the degree of accuracy and reliability appropriate to the work in question. However since the partners have no control over the use to which the information contained within the report is to be put by any other party, any other such party shall be deemed to have satisfied itself as to the suitability and reliability of the information in relation to any particular use, purpose or application. Under no circumstances will any of the partners, their servants, employees or agents accept any liability whatsoever arising out of any error or inaccuracy contained in this report (or any further consolidation, summary, publication or dissemination of the information contained within this report) and/or the connected work and disclaim all liability for any loss, damage, expenses, claims or infringement of third party rights. IST-1999-11729 METRA Doc. : IST-1999-11729/AAU-WP2-D2-V1.1. doc Title: MIMO Channel Characterisation 8 February, 2001 File: AAU-WP2-D2-V1.1. doc Page 5 of 57 0 EXECUTIVE SUMMARY . 2 1 ABBREVIATIONS. 7 2 INTRODUCTION . 8 3 STOCHASTIC MODELLING. 10 3.1 DESCRIPTION OF THE PROPOSED STOCHASTIC MODEL. 10 3.2 DESCRIPTION OF THE COSSAP IMPLEMENTATION. 12 3.2. 1 General description. 12 3.2. 2 Fast fading . 13 3.2. 3 Spatial correlation. 15 3.2. 4 Steering matrix . 16 3.2. 5 Interface documentation . 17 3.2. 6 Distribution. 19 3.2. 7 Web site . 19 4 PROPAGATION ISSUES. 20 4.1 POWER-AZIMUTH SPECTRUM (PAS) AND CORRELATION MATRICES. 20 4.2 DOPPLER SPECTRUM. 22 4.3 POWER-DELAY SPECTRUM (PDS) . 23 5 EXPERIMENTAL HARDWARE AND GEOMETRY. 25 5.1 THE MEASUREMENT SET-UP . 25 5.1. 1 General description. 25 5.1. 2 The stand alone testbed. 27 5.1. 3 Mechanical hardware and measurement procedure. 29 5.2 DESCRIPTION OF THE INVESTIGATED ENVIRONMENTS. 31 5.3 ANTENNA TOPOLOGIES . 33 5.3.1 Mutual coupling effect. 33 5.3.2 Compensation of the mutual coupling . 34 5.3. 3 Influence of the radiation pattern on the correlation coefficient. 36 6 MODEL VALIDATION . 38 6.1 GENERAL DESCRIPTION. 38 6.2 THE EIGENANALYSIS METHOD . 38 6.3 VALIDATION PROCEDURE . 39 6.4 ANALYSIS PROCEDURE . 39 6.5 GLOBAL VALIDATIONS. 41 6.5.1 cdfs . 41 6.5.2 2 order validation . 44 7 CONCLUSIONS . 46 8 REFERENCES. 47 9 APPENDIX 1 VALIDATION MODEL PAR