On Training Sequence Optimization for Leaked MIMO OFDM Channels

In this paper, the Cramér Rao bound (CRB) on the time-varying narrowband leaked Multiple-Input Multiple- Output Orthogonal Frequency Division Multiplexing (MIMO OFDM) channel estimators is derived, under the assumption of deterministic sequences. The CRB is proven to be effectively decoupled in delay and Doppler domains. Fixed point equations for determining the optimal training sequences for the decoupled CRB are provided. Doppler- optimized training sequences are shown to be whiter. Optimized sequences exhibit a performance gain on the order of 5 dB and 2.5 dB over purely random sequences used for training for Doppler and delay, respectively.

[1]  S. Kay.  Fundamentals of statistical signal processing: estimation theory , 1993 .

[2]  Holger Rauhut,et al.  Multichannel-compressive estimation of doubly selective channels in MIMO-OFDM systems: Exploiting and enhancing joint sparsity , 2010, 2010 IEEE International Conference on Acoustics, Speech and Signal Processing.

[3]  B.D. Rao,et al.  Complex constrained CRB and its application to semi-blind MIMO and OFDM channel estimation , 2004, Processing Workshop Proceedings, 2004 Sensor Array and Multichannel Signal.

[4]  H. Luetkepohl.  The Handbook of Matrices , 1996 .

[5]  Cleve Moler,et al.  Mathematical Handbook for Scientists and Engineers , 1961 .

[6]  Hans G. Feichtinger,et al.  Compressive tracking of doubly selective channels in multicarrier systems based on sequential delay-Doppler sparsity , 2011, 2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP).

[7]  Lang Tong,et al.  Optimal design and placement of pilot symbols for channel estimation , 2001, 2001 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No.01CH37221).

[8]  C. Loan,et al.  Approximation with Kronecker Products , 1992 .

[9]  Kaare Brandt Petersen,et al.  The Matrix Cookbook , 2006 .

[10]  Alfred O. Hero,et al.  Lower bounds for parametric estimation with constraints , 1990, IEEE Trans. Inf. Theory.

[11]  Urbashi Mitra,et al.  On the Cramér-Rao Bound of Time-Varying Narrowband Leaked MIMO OFDM Channels , 2018, 2018 IEEE 19th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC).

[12]  Bhaskar D. Rao,et al.  Sparse channel estimation via matching pursuit with application to equalization , 2002, IEEE Trans. Commun..

[13]  Stephen P. Boyd,et al.  Convex Optimization , 2004, Algorithms and Theory of Computation Handbook.

[14]  Sunav Choudhary,et al.  Bilinear Matrix Factorization Methods for Time-Varying Narrowband Channel Estimation: Exploiting Sparsity and Rank , 2018, IEEE Transactions on Signal Processing.

[15]  Brian M. Sadler,et al.  Bounds on SIMO and MIMO Channel Estimation and Equalization with Side Information , 2002, J. VLSI Signal Process..

[16]  Milica Stojanovic,et al.  Sparse equalization for real-time digital underwater acoustic communications , 1995, 'Challenges of Our Changing Global Environment'. Conference Proceedings. OCEANS '95 MTS/IEEE.

[17]  Phillipp Meister,et al.  Statistical Signal Processing Detection Estimation And Time Series Analysis , 2016 .

[18]  Pablo A. Parrilo,et al.  The Convex Geometry of Linear Inverse Problems , 2010, Foundations of Computational Mathematics.

[19]  Urbashi Mitra,et al.  Sparsity and Rank Exploitation for Time-Varying Narrowband Leaked OFDM Channel Estimation , 2018, 2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP).

[20]  Urbashi Mitra,et al.  Sparse Channel Estimation with Zero Tap Detection , 2007, IEEE Transactions on Wireless Communications.

[21]  K. Drouiche,et al.  A new test for whiteness , 2000, IEEE Trans. Signal Process..

[22]  Holger Rauhut,et al.  Compressive Estimation of Doubly Selective Channels in Multicarrier Systems: Leakage Effects and Sparsity-Enhancing Processing , 2009, IEEE Journal of Selected Topics in Signal Processing.

[23]  Urbashi Mitra,et al.  Nested Sparse Approximation: Structured Estimation of V2V Channels Using Geometry-Based Stochastic Channel Model , 2014, IEEE Transactions on Signal Processing.

[24]  Urbashi Mitra,et al.  Single-user sparse channel acquisition in multiuser DS-CDMA systems , 2003, IEEE Trans. Commun..