Low-density parity-check (LDPC) codes and convolutional Turbo codes are two of the most powerful error correcting codes that are widely used in modern communication systems. In a multi-mode baseband receiver, both LDPC and Turbo decoders may be required. However, the different decoding approaches for LDPC and Turbo codes usually lead to different hardware architectures. In this paper we propose...

Introduction: The complex geometry of breast and also lung and heart inhomogeneities near the planning target volume (PTV) result in perturbations in dose distribution. This problem can result in overdosage or underdosage in the match region of the three treatment fields. The purpose of this study is to create a homogeneous dose distribution in the match region between the supraclavicular and t...

This paper presents the characteristics of an integrated circuit called "turbo4" which can be used as a turbo-encoder or as a turbo-decoder. The turbo-encoder is built using a parallel concatenation of two recursive systematic convolutional codes with constraint length K=5. The turbo-decoder is cascadable, each circuit processing one iteration of the turbo-decoding algorithm. It is designed aro...

ETRI Journal, Volume 28, Number 5, October 2006 ABSTRACT⎯The effect of block interleaving in a low density parity check (LDPC)-turbo concatenated code is investigated in this letter. Soft decoding can be used in an LDPC code unlike the conventional Reed-Solomon (RS) code. Thus, an LDPC-turbo concatenated code can show better performance than the conventional RS-turbo concatenated code. Furtherm...

Reliable wireless broadcast with asynchronous data access based on fountain coding is investigated. We review the traditional problem formalisation for fountain codes operating on erasure channels, and we generalise the problem formalisation to more general channels. We introduce a novel type of rateless codes based on the Turbo Principle: the Turbo-Fountain. The Turbo-Fountain is able to consi...

We construct new families of error-correcting codes based on Gallager’s low-density parity-check codes. We improve on Gallager’s results by introducing irregular parity-check matrices and a new rigorous analysis of hard-decision decoding of these codes. We also provide efficient methods for finding good irregular structures for such decoding algorithms. Our rigorous analysis based on martingale...

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The spectacular performance offered by turbo codes sparked intense interest in them. A considerable amount of research has simplified, formalized, and extended the ideas inherent in the original turbo code construction. Nevertheless, the nature of the relatively simple ad hoc turbo-decoding algorithm has remained something of a mystery. We present a geometric interpretation of the turbo-decodin...

In this paper, secure channel coding schemes based on turbo codes are suggested for time reversal ultra wideband (TR-UWB) systems. Turbo code has the capability of error correction near Shannon’s limit. Adding security to turbo code is an attractive idea since it could reduce the overall processing cost of providing secure coded data and enjoys the advantages of high-speed encryption and decryp...