Characteristics of MIMO-OFDM Channels in Indoor Environments

We present the results of multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) channel measurements. The measurements were performed in indoor environments using four transmitters and four receivers with 40 MHz bandwidth at 5.25 GHz. Our measurements reveal two-dimensional small-scale fading, and correlation between MIMO subchannels. In the line-of-sight (LoS) case, the MIMO-OFDM channel capacity is found to be strongly dependent on the local scattering environment; and much less dependent in the non-LoS (NLoS) case. Also, MIMO channel capacity is found to be largely uncorrelated over 20 MHz in NLoS, while a strong correlation is found over 40 MHz in some LoS environments. The validity of the conventional Kronecker correlation channel model is tested, along with a recently proposed joint correlation model. The effects of varying antenna element spacing are also investigated, taking into account such effects as mutual coupling, radiation efficiency, and radiation pattern.

[1]  Jinhong Yuan,et al.  Performance of MIMO-OFDM-BICM on Measured Indoor Channels , 2006, 2006 IEEE 63rd Vehicular Technology Conference.

[2]  H. Vincent Poor,et al.  On the capacity of multiple-antenna systems in Rician fading , 2005, IEEE Transactions on Wireless Communications.

[3]  Tim C. W. Schenk,et al.  Implementation of a MIMO OFDM-based wireless LAN system , 2004, IEEE Transactions on Signal Processing.

[4]  Babak Daneshrad,et al.  Indoor field measurements with a configurable multi-antenna testbed , 2004, IEEE Global Telecommunications Conference, 2004. GLOBECOM '04..

[5]  Michael A. Jensen,et al.  Mutual coupling in MIMO wireless systems: a rigorous network theory analysis , 2004, IEEE Transactions on Wireless Communications.

[6]  K. Pedersen,et al.  A stochastic multiple-input-multiple-output radio channel model for evaluation of space-time coding algorithms , 2000, Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152).

[7]  Björn E. Ottersten,et al.  Second order statistics of NLOS indoor MIMO channels based on 5.2 GHz measurements , 2001, GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270).

[8]  Preben E. Mogensen,et al.  A stochastic MIMO radio channel model with experimental validation , 2002, IEEE J. Sel. Areas Commun..

[9]  Michael A. Jensen,et al.  Experimental characterization of the MIMO wireless channel: data acquisition and analysis , 2003, IEEE Trans. Wirel. Commun..

[10]  Jack H. Winters,et al.  On the Capacity of Radio Communication Systems with Diversity in a Rayleigh Fading Environment , 1987, IEEE J. Sel. Areas Commun..

[11]  Robert W. Heath,et al.  Switching between diversity and multiplexing in MIMO systems , 2005, IEEE Transactions on Communications.

[12]  Frederick W. Vook,et al.  An experimental OFDM system for broadband mobile communications , 2001, IEEE 54th Vehicular Technology Conference. VTC Fall 2001. Proceedings (Cat. No.01CH37211).

[13]  A. Nix,et al.  Mutual coupling in multi-element array antennas and its influence on MIMO channel capacity , 2003 .

[14]  Mohamed-Slim Alouini,et al.  Capacity of MIMO Rician channels , 2006, IEEE Transactions on Wireless Communications.

[15]  Björn E. Ottersten,et al.  Modeling of wide-band MIMO radio channels based on NLoS indoor measurements , 2004, IEEE Transactions on Vehicular Technology.

[16]  N. Kita,et al.  Measurement of Demmel condition number for 2/spl times/2 MIMO-OFDM broadband channels , 2004, 2004 IEEE 59th Vehicular Technology Conference. VTC 2004-Spring (IEEE Cat. No.04CH37514).

[17]  Jon W. Wallace,et al.  Deficiencies of 'Kronecker' MIMO radio channel model , 2003 .

[18]  Cedric Nishan Canagarajah,et al.  A measurement based feasibility study of space-frequency MIMO detection and decoding techniques for next generation wireless LANs , 2002, 2002 Digest of Technical Papers. International Conference on Consumer Electronics (IEEE Cat. No.02CH37300).

[19]  R. Janaswamy.  Effect of element mutual coupling on the capacity of fixed length linear arrays , 2002, IEEE Antennas and Wireless Propagation Letters.

[20]  Larry J. Greenstein,et al.  Moment-method estimation of the Ricean K-factor , 1999, IEEE Communications Letters.

[21]  Joseph M. Kahn,et al.  Fading correlation and its effect on the capacity of multielement antenna systems , 2000, IEEE Trans. Commun..

[22]  R.W. Heath,et al.  Rapid MIMO-OFDM software defined radio system prototyping , 2004, IEEE Workshop onSignal Processing Systems, 2004. SIPS 2004..

[23]  Donald C. Cox,et al.  Effect of antenna polarization on the capacity of a multiple element system in an indoor environment , 2002, IEEE J. Sel. Areas Commun..

[24]  Ernst Bonek,et al.  A stochastic MIMO channel model with joint correlation of both link ends , 2006, IEEE Transactions on Wireless Communications.

[25]  Theodore S. Rappaport,et al.  Wireless communications - principles and practice , 1996 .

[26]  Donald C. Cox,et al.  Correlation analysis based on MIMO channel measurements in an indoor environment , 2003, IEEE J. Sel. Areas Commun..

[27]  Geoffrey Ye Li,et al.  Broadband MIMO-OFDM wireless communications , 2004, Proceedings of the IEEE.

[28]  Matthew R. McKay,et al.  General capacity bounds for spatially correlated Rician MIMO channels , 2005, IEEE Transactions on Information Theory.