Joint spatial and temporal channel-shortening techniques for frequency selective fading MIMO channels

It is well understood that the maximum likelihood estimator is a powerful equalisation technique for frequency selective fading channels, and in particular for MIMO systems. The complexity of this estimator, however, grows exponentially with the number of users and multipath taps, hence limiting the use of this algorithm in MIMO systems. In the paper, the authors propose a joint spatial and temporal channel-shortening filter as a pre-processor to reduce significantly the complexity of a maximum likelihood estimator. Their design is based on both minimum mean square error and maximum signal-to-noise ratio criteria. They compare the performance of their proposed schemes with the existing methods that employ channel-shortening techniques only in the spatial or temporal dimension, and thereby demonstrate the advantage of using joint spatial and temporal channel shortening in terms of complexity and bit error rate performance.


Triple stub circuit topology as simultaneous insertion phase, amplitude and impedance control circuit for phased array applications
Unlu, M.; Demir, Şimşek; Akın, Tayfun (Institution of Engineering and Technology (IET), 2012-10-23)
This study shows that the well-known triple stub circuit topology can also be used for controlling the insertion phase and amplitude of a given signal simultaneously, as well as preserving its impedance transformation ability. The triple stub circuit topology, which is nothing but an extension of the conventional double stub loaded-line phase shifter, results in one more degree of freedom to its solution when it is solved for its insertion phase. This additional degree of freedom not only brings the impedan...
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Azizoglu, SA; Koç, Seyit Sencer; Buyukdura, OM (Institute of Electrical and Electronics Engineers (IEEE), 2004-03-01)
The importance of expanding Green's functions, particularly free-space Green's functions in terms of orthogonal wave functions is practically self-evident when frequency domain scattering problems are of interest. With the relatively recent and widespread interest in time-domain scattering problems, similar expansions of Green's functions are expected to be useful in the time-domain. In this paper, an expression, expanded in terms of orthogonal spherical vector wave functions, for the time-domain free-space...
Design of Maisel sidelobe blankers with a guarantee on the gap to optimality
COŞKUN, Osman; Candan, Çağatay (Institution of Engineering and Technology (IET), 2016-11-01)
The conventional sidelobe blanking system, known as the Maisel sidelobe blanker, uses two receiving channels with different gains to detect the presence of a jammer. The Maisel system is an ad-hoc detector without any optimality properties. Yet, it has been successfully utilised in numerous operational systems. Here, the authors study the optimum Neyman-Pearson type sidelobe blanking (SLB) detectors for the Swerling target models to assist the design of Maisel blankers. The authors note that the optimal sid...
Joint frequency offset and channel estimation
Avan, Muhammet; Candan, Çağatay; Department of Electrical and Electronics Engineering (2008)
In this thesis study, joint frequency offset and channel estimation methods for single-input single-output (SISO) systems are examined. The performance of maximum likelihood estimate of the parameters are studied for different training sequences. Conventionally training sequences are designed solely for the channel estimation purpose. We present a numerical comparison of different training sequences for the joint estimation problem. The performance comparisons are made in terms of mean square estimation err...
Methodology for performance analysis of randomly-spread CDMA systems over multipath fading channels via crosscorrelation matrix non-asymptotic average eigenvalue densities
Ertug, O; Baykal, Buyurman; Unal, BS (Institution of Engineering and Technology (IET), 2003-08-07)
A new methodology for closed-form theoretical performance analysis of randomly-spread CDMA systems over multipath fading channels with multiuser receivers is presented. The basis of the analysis is the representation of the random signal to interference ratios at finite system parameters in terms of the eigenvalues of crosscorrelation matrices for which the non-asymptotic average densities are found or known, The methodology presented complements the asymptotic Ruining theory used in similar previous work o...
Citation Formats
C. Toker, J. Chambers, and B. Baykal, “Joint spatial and temporal channel-shortening techniques for frequency selective fading MIMO channels,” IEE PROCEEDINGS-COMMUNICATIONS, pp. 89–94, 2005, Accessed: 00, 2020. [Online]. Available: