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Ste gano graphic systems are used for the transmission of hidden data in the original signal. The article describes the algorithm of the hidden data transmission using the speech signal as a carrier. The echo method is used for data embedding. In order to improve the decoding efficiency of embedded data, the procedure of voicing correction and mechanism of informed coding were developed and implemented...
For practical applications in forward error correction, the importance of a systematic codeword cannot be overemphasized. Thus, this paper proposes the construction of a systematic quasi-cyclic (QC) LDPC code. This systematic structure is achieved by a row reduction technique different from the conventional Gaussian elimination method. This row reduction technique has the advantage of being easier...
Compressed sensing (CS) has drawn many interest in the field ultrasound (US) image recovery. It has demonstrated promising results in the recovery of radio-frequency element raw-data [Liebgott et. al. ULTRAS13, Besson et. al. SPARS17]. The objective of such approaches is to recover the raw-data from undersampled random measurements. It is achieved by means of convex optimization or greedy methods...
This paper proposes Raptor codes-structured wireless super-dense networks serving a massive number of users with passive nodes constructing a precode of Raptor codes for future wireless networks. Passive nodes do not have their own information and only forward information from the neighboring nodes to the destination node. Similar to the capability of precode of Raptor coding scheme to protect information...
The possibility of describing the encoding and decoding procedures Bose-Chaudhuri-Hocquenghem codes using the summation operations modulo 2 is researched. This allows you to simplify these procedures and improve efficiency by correcting the error of the triplicate. There identified coding equations and triangular match tables: the syndrome — the distortion of the position.
We describe a successive cancellation list CRC (Cyclic Redundancy Check)-aided decoder for polar codes over AWGN (Additive White Gaussian Noise) Channel, Fading Channel and Impulsive Noise Channel. Simulation results show the advantage of this decoding method over the original proposed by Arikan.
In this paper wireless communications network is considered to transmit source information to destination. N number sources transmitting data to a destination receiver, through M relays nodes by employing random linear network coding (RLNC). Two methods of failure decoding probability on performance of wireless communication are explained and discussed in this paper. The major parameter that will...
Recent work in video compression has shown that using multiple 2D transforms instead of a single transform in order to de-correlate residuals provides better compression efficiency. These transforms are tested competitively inside a video encoder and the optimal transform is selected based on the Rate Distortion Optimization (RDO) cost. However, one needs to encode a syntax to indicate the chosen...
In this paper, a high speed digital excess loop delay (ELD) compensation scheme with hybrid thermometer coding is proposed. In this high speed compensation, the time constraint of the DAC feedback route is shifted to the one clock compensation path. Also, the method to deal with the signal overflows the quantizer's range is analyzed. Compared to other digital ELD compensations, this scheme features...
Transrating is a bitrate transcoding technique that facilitates video applications in heterogeneous environments. This paper presents a fast coding-unit (CU) mode decision algorithm for transrating a once-encoded HEVC bitstreams to lower bitrate versions of diverse quality levels. The proposed method comprises three major parts. First, an early SKIP decision is based on the modes and motion vectors...
We define a multiaccess communication scheme that effectively eliminates interference and resolves collisions in many-to-one and many-to-many communication scenarios. Each transmitter is uniquely identified by a coding vector. Using these vectors, all signals issued from a specific transmitter will be aligned along a unique dimension at all receivers hearing this transmission. This dimension is characteristic...
In this work, we show that polar belief propagation (BP) decoding exhibits an error floor behavior which is caused by clipping of the log-likelihood ratios (LLR). The error floor becomes more pronounced for clipping to smaller LLR-values. We introduce a single-value measure quantifying a “relative error floor”, showing, by exhaustive simulations for different lengths, that the error floor is mainly...
The inherent nature of polar codes being channel specific makes it difficult to use them in a setting where the communication channel changes with time. In particular, to be able to use polar codes in a wireless scenario, varying attenuation due to fading needs to be mitigated. To the best of our knowledge, there has been no comprehensive work in this direction thus far. In this work, a practical...
The RTCA DO-260B document has stimulated since a few years ago the adoption of novel algorithms to improve the ability of receivers to detect and decode ADS-B signals, with particular emphasis on preamble detection, declaration of bit state and confidence level, detection and correction of errors. Motivated by an industry-driven project, this paper reports on performance analysis of a set of enhanced...
Data representation plays an important role in performance of machine learning algorithms. Since data usually lacks the desired quality, many efforts have been made to provide a more desirable representation of data. Among many different approaches, sparse data representation has gained popularity in recent years. In this paper, we propose a new sparse autoencoder by imposing the power two of smoothed...
In this paper, we study an Electroencephalography (EEG) based biometric authentication system with privacy protection. We use motor imagery EEG, recorded using a wearable wireless device, as our biometric modality. To obtain EEG-based authentication keys we employ the fuzzy-commitment like scheme with soft-information at the decoder, see Ignatenko and Willems [2014]. In this work we study the effect...
We investigate secure communication over a channel under two different classes of attacks at the same time: a passive eavesdropper and an active jammer. This scenario is perfectly modeled by the concept of arbitrarily varying wiretap channels (AVWCs). It has been shown that uncorrelated codes are not always capable of overcoming the various jamming attacks. On the other hand, correlated random codes...
In this paper, we propose a chaotic convolutional encryption scheme based on multiple chaos mapping. The scheme employs the characteristics of pseudo randomness and sensitivity to initial conditions of chaos mapping. It generates time-varying state transition matrix through modulo-two adder between multiple chaos sequences and input data as well as the state values of status registers in convolutional...
In order to improve the error resistance and security of JPEG2000 standard, a joint source channel and security arithmetic coding/decoding scheme for EBCOT in JPEG2000 is proposed. Based on error resistant arithmetic coding, this scheme inserts multiple forbidden symbols and generates secure two-way decodable bitstream controlled by chaotic maps, improving the security of the scheme. Meanwhile, at...
In this paper, the iterative learning control problem using uniform quantizer with encoding and decoding scheme is considered, in which the system output is transformed and encoded firstly, and then transmitted back to the controller and decoded for input updating. Zero-error convergence of the output to the desired reference is realized by utilizing this updating scheme. The results are extended...
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