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Adaptive network coded cooperation (ANCC) scheme has been shown to have better performance than the conventional repetition-based schemes and the space-time coded cooperation (STCC) frameworks for data transmissions from a large collection of terminals to a common destination in large wireless networks. However, the random selection strategy for ANCC protocol may generate many short cycles in the...
This paper investigates the transmission in time dispersive channels of Spectrally Efficient Frequency Division Multiplexed (SEFDM) signals, where carrier orthogonality is intentionally violated in order to increase bandwidth efficiency. Sufficient statistics of the transmitted SEFDM signal can be obtained by projecting the received signal onto an orthonormal base generated at the receiver using an...
In wireless networks, designing transmission schemes adapting to time varying channel conditions is key to achieve better spectral efficiency. The design of such schemes for multi-hop wireless networks requires coordination among nodes in the network, which is achieved through feedback between nodes. Spectral efficiency can be improved for such networks by designing transmission schemes with limited...
This paper addresses the issue of encoding of LDPC codes for certain transmission standards that employ LDPC as coding scheme. It is shown that for these LDPC codes, the encoding can be done simply by reusing decoding resources with negligible overhead. Compared to conventional encoding designs, our approach requires much less resources specified for encoder.
Cooperative decoding is powerful technique for establishing good quality TV broadcasting. In cooperative decoding, some TV receivers, nodes, are cooperated, each other. These share the received information signal and thus obtain good quality information signal. Incremental-Maximum Ratio Combining (I-MRC) is one of the cooperative decoding methods. In I-MRC, the best condition's node and second one...
In energy harvesting communication systems, an exogenous recharge process supplies energy for the data transmission and arriving energy can be buffered in a battery before consumption. Transmission is interrupted if there is not sufficient energy. We address communication with such random energy arrivals in an information-theoretic setting. Based on the classical additive white Gaussian noise (AWGN)...
Since the pioneering research work of Ahlswede et al. in 2000, Network Coding (NC) has rapidly emerged as a major research area in electrical engineering and computer science due to its wide applicability to communication through real networks. The many contributions available in the literature to date, ranging from pure theoretical studies on fundamental limits to practical experimentations in real-world...
Lattice reduction algorithms, such as the LLL algorithm, have been proposed as preprocessing tools in order to enhance the performance of suboptimal receivers in MIMO communications. In this paper we introduce a new kind of lattice reduction-aided decoding technique, called augmented lattice reduction, which recovers the transmitted vector directly from the change of basis matrix, and therefore doesn't...
Communications usually do not have enough security. One of the ways for making the data secure is using methods for coding the information in a special manner. In this article one of the algorithms of coding and decoding information has been reviewed and explained. Coding is converting information to the form of coded text and decoding is the operation of converting coded information to the original...
In this paper a modified Offset Min-Sum decoding algorithm for Low-Density Parity Check Codes is presented. In this modified algorithm, the offset factor in the original Offset Min-Sum algorithm is adjusted iteratively with the assistance of the check-node computation outputs of the Normalized Min-Sum algorithm. As a result, the offset factor in our modified algorithm can be calculated adaptively...
The computational complexity of H.264 video coding standard is two or three times higher than that of H.263 and MPEG-4. Especially, the operations of the entropy coding and deblocking filter are the most complex parts in the decoder. In order to reduce the computational complexity of these operations, we propose a fast algorithm for H.264 decoder implementation, which containing a group-based CAVLC...
This research paper discussed the usage of watermarking in medical images to ensure the authenticity and integrity of the image and reviewed some watermarking schemes that had been developed. A design of a reversible tamper detection and recovery watermarking scheme was then proposed. The watermarking scheme uses a 640×480×8 bits ultrasound grayscale image as a sample. The concept of ROI (Region Of...
RA (Repeat Accumulate) code has been widely used in wireless communication systems. But the BP (Belief Propagation) decoding algorithm which is commonly used in RA Code has high complexity. In order to reduce the complexity of BP algorithm while maintaining coding performance, we proposed Chebyshev-Polynomial-Fitting based BP (CPF-BP) decoding algorithm. In CPF-BP decoding algorithm, we used polynomial...
Fractal image compression is a relatively recent image compression method. Its basic idea is to represent images as a fixed point of a contractive Iterated Function System. Spiral Architecture is a novel image structure on which images are displayed as a collection of hexagonal pixels. But till date there are no available image capture or display devices to support this structure. Hence in order to...
Aiming the deficiency of control performance of existing traffic signal controller, we finish whole design of intelligent traffic signal controller based on MPC8245 processor and Hard Hat Linux kernel. After designing minimum system of MPC8245, we extend Compact PCI bus so as to finish video capture, network communication, and serial communication utilizing all kinds of PCI card. In our systems we...
Medium Grain Scalable (MGS) coding is widely used as the quality scalable video coding (SVC) method. In this paper, we study bitstream extractor for MGS-based bitstream. In MGS, the coded data corresponding to a quantization step size can be fragmented into at most 15 sub-layers, which is called MGS slices. The contribution of each slice to the video quality is evaluated by our proposed algorithm,...
Because various machine translation (MT) systems adopt different language rules and statistical methods, their performances are different. To combine different MT systems and make full use of their advantages so as to improve comprehensive performance of the combination MT system, has become an important development trend in the research field. This paper divides the current combination methods into...
This paper designs an RFID IP core by utilizing FPGA technology, which has advantages of internal task scheduling and high-speed encoding & decoding. The RTL design of base-band communication IP core based on modular method is presented. The RFID simulation model is established and the experiment results show that the proposed communication simulation model has a good performance, and the IP-core...
We consider in this paper the problem of blind frame synchronization of systems using Reed-Solomon (RS) codes and other related families. We present first of all three techniques of blind frame synchronization based on the non-binary parity check matrix of RS codes. While the first two techniques involve the calculation of hard and soft values of the syndrome elements respectively, the third one perform...
Cooperation diversity schemes employing space-time block coding (STBC) techniques have been proposed for wireless networks to increase systems capacity and coverage, by allowing multiple relay nodes distributed in space to assist the transmission between a given pair of terminals. Conventional relaying strategies, such as amplify-and-forward (A&F) and decode-and-forward (D&F), are designed...
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