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The smart antennas-MIMO (SA-MIMO) system combines MIMO and smart antennas by replacing each antenna of MIMO with a smart antenna array. For the general case, it is difficult to derive closed-form solutions of the optimal beamforming vectors to the capacity optimization problem of the SA-MIMO system. In this paper, the Particle Swarm Optimization (PSO) algorithm is presented for determining the suboptimal...
In this article, we proposed a robust adaptive algorithm for PN code acquisition and beamforming in direct sequence spread spectrum (DSSS) system with antenna arrays. Two adaptive filters are employed in the DSSS system, one is a spatial filter acting as a beamformer and the other is a temporal filter acting as a PN code-delay estimator. The cost function of LMS adaptive algorithm is given by constraining...
Space Shift Keying (SSK) modulation combined with Multiple-Input-Multiple-Output (MIMO) technique is an entirely novel modulation concept that utilizes the spatial domain for communication. In this scheme, several transmitters are used for data transmission, but only one transmitter is active at any time instance, which can be implemented by establishing a one-to-one mapping between the information...
According to the chaotic characteristics of frequency hopping (FH) sequences and the short-term predictability of Chaos, this paper presents an improved Bayesian network predictive model applied to FH sequences prediction. Firstly, the model regards the entire reconstructed phase space as a prior data information; Then, according to the characteristic of FH sequences which consist of multiple frequency...
We propose multihoming, the token synchronization, and the packet selection in FL-net to achieve fault tolerance. Multihoming assigns two IPs on two interfaces which reach two disjoint paths so that 1 + 1 packets in FL-net for the 1 + 1 protection architecture are supported. However, based on the architecture, a problem called delay mismatch makes FL-net nondeterministic because of collisions. To...
In this paper, we introduce a new framework for Intra-Frame spatial error concealment. It is based on a method of multi-level matching which divides the lost areas into several sections and recovers every section by adaptive interpolation. It contains three steps: 1) A line growing based segmentation algorithm is used to detect the edge points in the neighbouring lines of the lost areas; 2) A multi-level...
The convergence characteristics of a proposed iterative method for computing EM wave scattering from three-dimensional (3D) perfectly conducting objects are investigated and compared to those of conventional iterative schemes. The Buffered Block Forward Backward Method (BBFM) and an improved version is shown to be better than the Generalized Minimal Residual Method (GMRES) and the Biconjugate Gradient...
Low-density parity-check (LDPC) codes are widely applied in modern communication system for its capability of approaching channel capacity at low complexity. We design an efficient encoding scheme based on LU decomposition for China mobile multimedia broadcasting (CMMB). We search for element with lightest row-multiplying-column weight from the k th row and k th column, and exchange it with diagonal...
Adaptive power allocation subject to the total power constraint in an end-to-end cooperative orthogonal frequency Division multiplexing (OFDM) system is studied, with the optimal power allocation in terms of maximizing the sum transmission Rate being derived. The conventional two-hop system model is extended to a three-hop structure in this paper to improve the Wireless coverage. Independent and identically...
The Modal Distribution (MD) is a time-frequency distribution specifically designed to model the quasi-harmonic, multisinusoidal, nature of music signals and belongs to the Cohen general class of time-frequency distributions. Signal synthesis from bilinear time-frequency representations such as the Wigner distribution has been based on methods which exploit an outer-product interpretation of these...
In recent years, a new internet architecture based on the publish/subscribe paradigm has been adopted by organizations such as the FP7 EU project PSIRP (Publish/Subscribe Internet Paradigm) and its follow on FP7 EU project PURSUIT (Publish/Subscribe Internet Technology). Furthermore, a publish/subscribe based zFilter forwarding node has been developed and implemented on the NetFPGA platform. The zFilter...
Data retrieval problem is a novel research direction about wireless data broadcast. The goal is to find an efficient sequence to download the requested information from public information in wireless communication. The types of data items broadcast in channel are followed: consecutive and no replicated, non-consecutive and no replicated, and non-consecutive and replicated. The goal of above types...
The model of sound scattering by elastic cylindrical shell is built and the mathematical expressions of sound pressure and velocity are deduced. Then the influences of sound scattering on the directivity of vector sensor are simulated at different incident frequencies, shell thicknesses and observing distances. The result shows that when the incident frequency is close to the resonating frequency,...
For high-speed satellite communication system, the symbol rate of the modulated signal is usually high. However, the reliable working clock frequency of the commonly used digital processing chips is relatively lower, thus we should use parallel demodulation structure to achieve high-speed demodulation. A frequency-domain parallel demodulation structure combining matched filter with timing synchronization...
The selection of relaying node has an important influence on the D2D system performance. Previous literatures always utilize one selection strategy and consider only the reliability of the system. The strategy we propose determines which relay scheme to use according to the specific communication context. After the best relaying node is determined, we do the power allocation for that best relay for...
The Wideband Global SATCOM (WGS) system is being developed to provide the ability of flexible band-switching in satellite, so-called “any coverage to any coverage”. With the digital channelizer transponder used in, the transponder power gain of individual links could be adjusted respectively. Heterogeneous gain states can be especially useful for balancing the needs of dissimilar links in the same...
In this paper, we propose a new approach for building mission-critical systems with an emphasis on intrusion tolerance. The fundamental mechanisms employed in this approach includes: (1) The separation of execution and state management, which enables the use of a single process to manage application requests, thereby reducing runtime overhead and enables highly concurrent executions. (2) The append-only...
A novel image segmentation algorithm based on the HSI color space and an improved mean shift is proposed. The current work is discussed form two perspectives, i.e., the color space more suitable for human being's perception is selected and the segmentation algorithm is improved sufficiently. Unlike many of the traditional algorithms, the proposed algorithm is nonparametric and does not require any...
Aiming at the detecting and tracking of the moving dim targets from image observations with low signal-to-noise ratio(SNR), this paper puts forward a new track-before-detect algorithm based on Gaussian particle filter implementation of Multi-Bernoulli filter (GPF-MB-TBD). GPF-MB-TBD can greatly reduce the requirement for storing, and improve the performance of tracking than the sequential Monte Carlo...
The performance of the best relay selection on the decode-and-forward (DF) mode cognitive radio relay networks is studied. Some important factors, such as the outage probability, the bit error ratio (BER), and the average channel capacity, are analysed in this paper. As compared to the conventional relay selection schemes, the impact of spectrum sensing process as well as the spectrum utilization...
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