Considering payload, reliability, security and operational lifetime as major constraints in transmission of images we put forward in this paper a steganographic technique implemented at the physical layer. We suggest transmission of Halftoned images (payload constraint) in wireless sensor networks to reduce the amount of transmitted data. For low power and interference limited applications Turb...

In space division multiplexing with orthogonal frequency division multiplexing (SDM–OFDM) systems, since co-channel interference (CCI) degrades the demodulation performance, CCI suppression is essential. For CCI suppression, the turbo detector using the soft-input softoutput maximum likelihood detector (SISO–MLD) is proposed. Although SISO–MLD can deal with soft information, SISO–MLD updates on...

In recent years, iterative processing techniques with soft-in/soft-out (SISO) components have received considerable attention. Such techniques, based on the so-called turbo principle, are exemplified through turbo decoding, turbo equalization and turbo multiuser detection. In this paper, turbo multiuser detection is applied to a discrete multitone (DMT) very-high-rate digital subscriber line (V...

Mobile WiMAX is a broadband wireless solution that enables convergence of mobile and fixed broadband networks through a common wide area broadband radio access technology and flexible network architecture. It adopts Orthogonal Frequency Division Multiple Access (OFDMA) for improved multi-path performance in Non-Line-Of-Sight (NLOS) environments. Scalable OFDMA (SOFDMA) is introduced in the IEEE...

The performance of turbo codes in quasi-static fading channels both with and without antenna diversity is investigated. In particular, simple analytic techniques that relate the frame error rate of a turbo code to both its average distance spectrum as well as the iterative decoder convergence characteristics are developed. Both by analysis and simulation, the impact of the constituent recursive...

This paper examines turbo codes that are currently introduced in many international standards, including the UMTS standard for third generation personal communications and the ETSI DVB-T standard for Terrestrial Digital Video Broadcasting. The convergence properties of the iterative decoding process associated with a given turbo-coding scheme are estimated using the analysis technique based on ...

The turbo-roundabout concept has recently emerged in the Netherlands as a viable alternative to conventional multilane roundabouts, aiming to solve a set of functional problems related to the weaving maneuvers in the entry and negotiation zones. Although this is a recent concept, the Dutch experience has been showing that it is an extremely efficient solution, mainly in terms of safety. In fact...

We proposed a new class of asymmetric turbo encoder for 3G systems that performs well in both “water fall” and “error floor” regions in [7]. In this paper, a modified (optimal) power allocation scheme for the different bits of new class of asymmetric turbo encoder has been investigated to enhance the performance. The simulation results and performance bound for proposed asymmetric turbo code wi...

This paper examines the problem of symbol timing recovery and decoding in turbo-coded systems. The large coding gain of Turbo-codes enables reliable communications at very low signal-to-noise ratio (SNR). However, the application of turbo coding exacerbates the problem of timing recovery due to its very low operating SNRs. Therefore we propose a new concept: ‘apriori probability aided’ symbol t...