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The characteristics of underwater acoustic channel is strong multipath, severe Doppler and limited bandwidth. OFDM modulation has good ability in anti multipath and Turbo Product Codes(TPC) has excellent performance in a high code rate, We make full use of their advantages and designed an OFDM underwater acoustic communication system based on TPC. Using the BELLHOP simulation model to get the approximate...
The most efficient transmission system of the transport network is OTN offered by ITU-T G.709. However, in this recommendation, there is no indication as to what degree of MQAM determining the number of points of signal constellation provides the maximum capacity of multichannel system. This work removes this gap.
The radio access technology for railway communications is expected to migrate from GSM for Railways (GSM-R) to a more suitable generation of communication systems for the services offered nowadays, like the fourth generation (4G) or the fifth generation (5G). Recently, considerable attention has been devoted to high-speed trains since this particular environment poses challenging problems in terms...
The deployment of smart grid communication networks (SGCN) in urban areas has been possible due to the huge availability of wired and wireless communication technologies. However, in rural areas, those communications options are usually not available, unsuitable and/or too costly, making the deployment of a SGCN more challenging in such a case. On the other hand, the recently introduced low power...
In this paper, an investigation of multiview video coding schemes is presented, based on different inter-view prediction structures and various group of pictures (GOP) sizes. The studied inter-view prediction schemes in this paper are: A new approach namely “PIP”, recently proposed (PBI), and the benchmark structure (MVC). Results of the conducted tests allow to order the studied inter-view structures...
In this paper, we mainly focus on the optimization of multi-level coded modulation scheme in terms of sub-channel code rate optimal assignment and irregular QC-LDPC code construction with the aid of EXIT chart analysis. Simulation results show that the proposed MLCM scheme can achieve additional 0.1dB NCG compared with the UEP coded modulation scheme.
We study the problem of constructing good spacetime codes for broadcasting K independent messages over a MIMO network to L users, where each user demands all the messages and already has a subset of messages as side information. As a first attempt, we consider the 2 × 2 case and propose golden-coded index coding by partitioning the golden codes into K subcodes, one for each message. The proposed scheme...
In this paper, an energy efficient coding scheme for the multiple access relay channel at a fixed desired sum rate is analyzed. We first introduce a coding scheme, then, derive an optimal set of power allocation, which minimizes the network energy consumption while maintaining a desired sum rate. The results show that this scheme significantly outperforms direct and two-hop transmission. Moreover,...
In this paper we propose a generalized concatenated code (GC code) construction based on shortened Reed-Solomon inner codes and nonbinary LDPC outer codes. We also propose a soft-input decoder for this construction that makes use of soft-input soft-output decoding of both inner and outer codes. We show that this construction gives significant coding gain. We also compared it to generalized error-location...
We experimentally studied the implementation of forward error correction in software defined radio access networks by means of transceivers based on USRP. We tested the system in a 2 m wireless link and obtain an improvement in the performance of 4 dB for BPSK and QPSK modulation formats and almost of 5 dB for 8-PSK when adding a Reed Solomon code (127, 123) for reducing the errors. A characterization...
Channel coding plays a vital role for the maintenance of quality and reliability in data delivery in a communication system. Practical applications of channel coding includes the area of deep space communication, satellite communication, wireless communication, data transmission etc. Convolution coding is one of large class among them. The main aim of this paper is to elucidate the main features of...
To improve the rate-distortion (RD) performance of low delay (LD) High Efficiency Video Coding (HEVC) encoding while enabling scene-based non-linear editing feature (NLEF), in this paper, we present a new scene-based LD HEVC encoding framework in which scene change (SC) detection and coding are conducted jointly. A frame in a sequence to be encoded is deemed a SC if there is a sudden change in the...
Demand for screen content videos that contain computer generated text and graphics is growing. They are very different from natural videos, because they include much sharper edge transitions and very repetitive patterns. On this type of material, the efficacy of the conventional discrete cosine transform (DCT) is questionable because it relies on the assumption that a Gauss-Markov model leads to a...
We introduce a new geometric shaping to optimize signal constellations maximizing generalized mutual information for both binary and nonbinary coding. With parametric projection of hyper cubes, we can perform seamless constellation shaping with near 1 dB gain.
The article discusses self-orthogonal error-correcting codes (SOC) for the decoding of which multithreshold algorithms (MTD) are usually used. To decode SOC the algorithms used for low-density parity-check (LDPC) codes can also be applied. The article shows that using a min-sum decoder for SOC over a channel with additive white Gaussian noise (AWGN) in case of binary phase shift keying allows to receive...
Galileo is studying the addition of Navigation Message Authentication (NMA) to its Open Service. NMA cryptographic data is mostly unpredictable, and this unpredictability can provide certain protection against replay attacks, depending on the user environment and how the signal is processed in the receiver. This paper first characterises Galileo NMA symbol unpredictability, which depends on how the...
In this paper, we investigate the application of spherical codes in a sparse code multiple access (SCMA) system. We use spherical codes to build multidimensional mother constellations for SCMA codebooks, to lower peak to average power ratio (PAPR) as well as to improve the overall spectrum efficiency. Furthermore, we introduce four approaches to construct good spherical codes. These codes are easy...
This paper considers multilevel multithreshold decoder for a self-orthogonal codes. Simulation results for an AWGN channel are reported. New modifications of this decoder provided coding gain improving by a few tenths of dB due to better using of the bits soft information are offered. Recommendations to choose the best algorithms of constituting blocks of the multilevel multithreshold decoder and...
Cooperative communication uses spatial diversity to mitigate multipath fading. With an appropriate assignment of partners it also decreases the energy expenditure of the network. Together with optimum transmit power allocation, it is a useful technique to overcome the energy constraint problem in wireless sensor nodes. The calculation of optimum power in a Rician fading channel is a computationally...
The advent of consumer-level plenoptic cameras has sparkled the interest towards the design of efficient compression techniques for light field images. State-of-the-art compression systems such as HEVC prove to be inefficient when directly applied on this type of data due to the inherent spatial discontinuities among neighboring microlens images. In this paper, a novel light field image compression...
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