Efficient communication over highly spread underwater acoustic channels
Proceedings of the second workshop on Underwater networks
Orthogonal structured linear dispersion code for fast sphere decoding
Proceedings of the 2009 International Conference on Wireless Communications and Mobile Computing: Connecting the World Wirelessly
Stopping criterion for complexity reduction of sphere decoding
IEEE Communications Letters
Quasi-maximum-likelihood detector based on geometrical diversification greedy intensification
IEEE Transactions on Communications
Stochastic MV-PURE estimator: robust reduced-rank estimator for stochastic linear model
IEEE Transactions on Signal Processing
Complex lattice reduction algorithm for low-complexity full-diversity MIMO detection
IEEE Transactions on Signal Processing
The error probability of the fixed-complexity sphere decoder
IEEE Transactions on Signal Processing
IEEE Transactions on Signal Processing
Implementation of a Markov chain Monte Carlo based multiuser/MIMO detector
IEEE Transactions on Circuits and Systems Part I: Regular Papers
New rate-2 STBC design for 2 TX with reduced-complexity maximum likelihood decoding
IEEE Transactions on Wireless Communications
Efficient receiver algorithms for DFT-spread OFDM systems
IEEE Transactions on Wireless Communications
A list-based detection technique for long intersymbol interference channels
IEEE Transactions on Wireless Communications
Tail behavior of sphere-decoding complexity in random lattices
ISIT'09 Proceedings of the 2009 IEEE international conference on Symposium on Information Theory - Volume 2
An efficient MIMO detection algorithm employed in imperfect noise estimation
WSEAS TRANSACTIONS on COMMUNICATIONS
IEEE Transactions on Communications
Reduced complexity sphere decoding via a reordered lattice representation
IEEE Transactions on Communications
On convex vector precoding for multiuser MIMO broadcast channels
IEEE Transactions on Signal Processing
Joint bit allocation and precoding for MIMO systems with decision feedback detection
IEEE Transactions on Signal Processing
A fast-decodable code structure for linear dispersion codes
IEEE Transactions on Wireless Communications
On overloaded vector precoding for single-user MIMO channels
IEEE Transactions on Wireless Communications
On further reduction of complexity in tree pruning based sphere search
IEEE Transactions on Communications
Approaching MIMO capacity using bitwise Markov chain Monte Carlo detection
IEEE Transactions on Communications
Low-complexity decoding via reduced dimension maximum-likelihood search
IEEE Transactions on Signal Processing
Efficient symbol detection in multi-device STBC-MIMO system
ISCIT'09 Proceedings of the 9th international conference on Communications and information technologies
APCC'09 Proceedings of the 15th Asia-Pacific conference on Communications
APCC'09 Proceedings of the 15th Asia-Pacific conference on Communications
Near-optimal detection in MIMO systems using Gibbs sampling
GLOBECOM'09 Proceedings of the 28th IEEE conference on Global telecommunications
A reduced-complexity MIMO receiver via channel ordering
GLOBECOM'09 Proceedings of the 28th IEEE conference on Global telecommunications
ICC'09 Proceedings of the 2009 IEEE international conference on Communications
Reconfigurable K-best algorithm for MIMO detection systems
ICICS'09 Proceedings of the 7th international conference on Information, communications and signal processing
Frequency estimation by phase unwrapping
IEEE Transactions on Signal Processing
PIC-based iterative SDR detector for OFDM systems in doubly-selective fading channels
IEEE Transactions on Wireless Communications
S/MIMO MC-CDMA Heuristic Multiuser Detectors Based on Single-Objective Optimization
Wireless Personal Communications: An International Journal
Maximum-likelihood noncoherent OSTBC detection with polynomial complexity
IEEE Transactions on Wireless Communications
Sarnoff'10 Proceedings of the 33rd IEEE conference on Sarnoff
An efficient low-complexity detector for spatially multiplexed MC-CDM
IEEE Transactions on Signal Processing
IEEE Transactions on Information Theory
Soft-input soft-output single tree-search sphere decoding
IEEE Transactions on Information Theory
Wireless Personal Communications: An International Journal
Matrix-lifting semi-definite programming for detection in multiple antenna systems
IEEE Transactions on Signal Processing
Performance and complexity analysis of infinity-norm sphere-decoding
IEEE Transactions on Information Theory
A fast constrained sphere decoder for ill conditioned communication systems
IEEE Communications Letters
Fast multi-symbol based iterative detectors for UWB communications
EURASIP Journal on Advances in Signal Processing - Special issue on advanced equalization techniques for wireless communications
Wireless Personal Communications: An International Journal
A List Sphere Decoding Algorithm with Improved Radius Setting Strategies
Wireless Personal Communications: An International Journal
Upper-Lower Bounded-Complexity QRD-M for Spatial Multiplexing MIMO-OFDM Systems
Wireless Personal Communications: An International Journal
Reduced complexity sphere decoding
Wireless Communications & Mobile Computing
Adaptive Parallel and Iterative QRDM Detection Algorithms for MIMO Multiplexing Systems
Wireless Personal Communications: An International Journal
Advances in Artificial Intelligence
Low-complexity dominance-based sphere decoder for MIMO systems
Signal Processing
Hi-index | 35.90 |
Sphere decoding has been suggested by a number of authors as an efficient algorithm to solve various detection problems in digital communications. In some cases, the algorithm is referred to as an algorithm of polynomial complexity without clearly specifying what assumptions are made about the problem structure. Another claim is that although worst-case complexity is exponential, the expected complexity of the algorithm is polynomial. Herein, we study the expected complexity where the problem size is defined to be the number of symbols jointly detected, and our main result is that the expected complexity is exponential for fixed signal-to-noise ratio (SNR), contrary to previous claims. The sphere radius, which is a parameter of the algorithm, must be chosen to ensure a nonvanishing probability of solving the detection problem. This causes the exponential complexity since the squared radius must grow linearly with problem size. The rate of linear increase is, however, dependent on the noise variance, and thus, the rate of the exponential function is strongly dependent on the SNR. Therefore sphere decoding can be efficient for some SNR and problems of moderate size, even though the number of operations required by the algorithm strictly speaking always grows as an exponential function of the problem size.