High-speed turbo-TCM-coded orthogonal frequency-division multiplexing ultra-wideband systems
EURASIP Journal on Wireless Communications and Networking
Iterative decoding of concatenated codes: a tutorial
EURASIP Journal on Applied Signal Processing
Convergence analysis of turbo decoding of serially concatenated block codes and product codes
EURASIP Journal on Applied Signal Processing
Iterative list decoding of concatenated source-channel codes
EURASIP Journal on Applied Signal Processing
An improved SIC based turbo equalizer
WSEAS TRANSACTIONS on COMMUNICATIONS
QoS-constrained opportunistic scheduling for SC-FDMA with iterative multiuser detection
IEEE Communications Letters
IEEE Transactions on Communications
Equal power allocation of IDMA systems: feasibility, optimality, and throughput
IEEE Transactions on Wireless Communications
Optimal puncturing ratios and energy allocation for multiple parallel concatenated codes
IEEE Transactions on Information Theory
Analysis of threshold of regular and irregular LDPC codes using Gaussian approximation
WTS'09 Proceedings of the 2009 conference on Wireless Telecommunications Symposium
Bit error rate estimation for turbo decoding
IEEE Transactions on Communications
IEEE Transactions on Communications
Belief propagation, Dykstra's algorithm, and iterated information projections
IEEE Transactions on Information Theory
IEEE Transactions on Communications
Partial multiuser detection for CS-CDMA/CP over multipath channels
IEEE Transactions on Communications
Semi-analytical performance prediction methods for iterative MMSE-IC multiuser MIMO joint decoding
IEEE Transactions on Communications
A Walsh-Hadamard coded spectral efficient full frequency diversity OFDM system
IEEE Transactions on Communications
Spectral efficient cooperative diversity technique with multi-layered modulation
IEEE Transactions on Communications
Performance of a high-speed concatenated coded modulation scheme over fading channels
MILCOM'03 Proceedings of the 2003 IEEE conference on Military communications - Volume I
VLSI architectures for sliding-window-based space-time turbo trellis code decoders
Journal of Electrical and Computer Engineering - Special issue on Implementations of Signal-Processing Algorithms for OFDM Systems
Hi-index | 0.19 |
We track the density of extrinsic information in iterative turbo decoders by actual density evolution, and also approximate it by symmetric Gaussian density functions. The approximate model is verified by experimental measurements. We view the evolution of these density functions through an iterative decoder as a nonlinear dynamical system with feedback. Iterative decoding of turbo codes and of serially concatenated codes is analyzed by examining whether a signal-to-noise ratio (SNR) for the extrinsic information keeps growing with iterations. We define a “noise figure” for the iterative decoder, such that the turbo decoder will converge to the correct codeword if the noise figure is bounded by a number below zero dB. By decomposing the code's noise figure into individual curves of output SNR versus input SNR corresponding to the individual constituent codes, we gain many new insights into the performance of the iterative decoder for different constituents. Many mysteries of turbo codes are explained based on this analysis. For example, we show why certain codes converge better with iterative decoding than more powerful codes which are only suitable for maximum likelihood decoding. The roles of systematic bits and of recursive convolutional codes as constituents of turbo codes are crystallized. The analysis is generalized to serial concatenations of mixtures of complementary outer and inner constituent codes. Design examples are given to optimize mixture codes to achieve low iterative decoding thresholds on the signal-to-noise ratio of the channel