This paper studies the performance of iterative multiuser decoding, interference cancellation, and channel estimation techniques applicable to third generation WCDMA systems. The concept uses a posteriori probabilities of code symbols to enhance detection, decoding and channel estimation in an iterative fashion. Performance is analyzed in a multi-path channel with simulations. It is seen that t...

We consider serially concatenated block codes in a hybrid ARQ scheme using iterative decoding. The extrinsic information generated in the iterative decoding process is saved and used when a retransmission is decoded. Two different strategies are examined; one using the extrinsic information only in the very first iteration, whereas the other uses it in all subsequent iterations until another re...

In this paper, we propose a new iterative detection and decoding scheme based on parallel interference cancel (PIC) for coded MIMO-OFDM systems. The performance of proposed receiver is improved through the joint PIC MIMO detection and iterative detection and decoding. Its performance is evaluated based on computer simulation. The simulation results indicate that the performance of the proposed ...

The turbo decoding algorithm of a decade ago constituted a milestone in error-correction coding for digital communications, and has inspired extensions to generalized receiver topologies, including turbo equalization, turbo synchronization, and turbo CDMA, among others. Despite an accrued understanding of iterative decoding over the years, the “turbo principle” remains elusive to master analyti...

The invention of turbo codes and low density parity check (LDPC) codes has made it possible for us for design error correcting codes with low decoding complexity and rates close to channel capacity. However, such codes have been studied in detail only for the most basic communication system, in which a single transmitter sends data to a single receiver over a channel whose statistics are known ...

In this contribution we derive the super-trellis structure of turbo codes. We show that this structure and its associated decoding complexity depend strongly on the interleaver applied in the turbo encoder. We provide upper bounds for the super-trellis complexity. Turbo codes are usually decoded by an iterative decoding algorithm, which is suboptimum. Applying the super-trellis structure, we ca...

Abstract. One-step iterative decoding for bit-interleaved coded QAM with conventional Gray mapping can give a significant improvement of performance for fading channels. Furthermore, iterative decoding with ideally known feed back bits is easier to analyze theoretically than non-iterative decoding. In this paper, we derive analytical expressions for the pairwise error probabilities for bit-inte...

Iterative decoding techniques have gain popularity due to their performance and their application in most communications systems. In this paper, we present a new application of our iterative decoder on the GPCB (Generalized Parallel Concatenated Block codes) which uses cyclic permutations. We introduce a new variant of the component decoder. After extensive simulation; the obtained result is ve...

Implementation constraints on iterative decoders applying message-passing algorithms are investigated. Serial implementations similar to traditional microprocessor datapaths are compared against architectures with multiple processing elements that exploit the inherent parallelism in the decoding algorithm. Turbo codes and low-density parity check codes, in particular, are evaluated in terms of ...

This paper outlines that when decoding an arbitrary analog block codes, i.e., a block codes over the complex or real numbers, in an iterative fashion by splitting the H-Matrix in two, leads to a least-squares estimate. Such a Turbo-like algorithm represents iterative projections in Euclidean space. A step size controls the convergence speed. The paper generalized an earlier result based on arra...