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Network coding is a new method by which a multicast network can achieve the network capacity determined by the max-flow and min-cut theorem. This paper shows the mutual exchange of independent information between two nodes in a wireless network which can be efficiently combined with network coding and broadcast property offered by wireless medium. It introduces COPE, an opportunistic approach to network...
The vehicle distribution problem has been a NP problem for a long time; it can not reach a most optimized state. Because of the multi-factors that should be considered about the vehicle distribution problem such as the loading capacity, sources , the cargo categories and so on. So it can not to describe it with one or a set of math expressions. This article based on the Genetic Algorithm takes each...
In this paper, we first analyze the amount of fading (AF) of orthogonal space-time block codes (STBCs) over spatially uncorrelated keyhole channels. In order to investigate the diversity order of keyhole channels, we then derive an approximate expression for the average bit error rate (BER) at high signal-to-noise ratio (SNR). Finally we present the average capacity expression by applying the Gauss-Laguerre...
Quantum communication system is influenced by environment noise in the whole process. Quantum error-correcting codes can solve this problem efficiently. The polynomial representation of a quantum state is defined. Based on the structure of the classical convolutional codes, the basis state of the quantum convolutional codes is transformed into the multiplication of an information polynomial by the...
Because most practical communication systems need possessing higher bandwidth efficiency, this article increases the bandwidth efficiency through the two aspects of code rate and modulation mode, that is, by combining CTC(convolutional turbo code) in WiMax protocol with MSK modulation and applying them in the practical communication systems. The simulation result shows the combination of CTC and MSK...
Video copyright protection is an important concern under the circumstances of network. A novel video watermarking algorithm is proposed according to the feature of DCT coefficients in I frame image on H.264. It generates watermark information using low frequency coefficients and embeds the watermark in middle frequency coefficients to make it robust and blind. This method needn't the original video...
Under the influence of the growth in ship scale, the container ports are in a highly competitive market environment. It should view berth allocation problems in a win-win perspective for container terminal operators and shipping companies.This paper puts forward that container ships with different TEUs capacity should be given different priorities in the process of berth allocation, and the larger...
Content analysis is generally regarded as a class of qualitative methodology that has been applied in such fields as history, journalism and anthropology. The paper discussed its applicability to service design as a kind of technique and incorporated it into service design toolkit. Taking mid-priced limited service hotels (MPLSH) for example, the article illustrated how content analysis could be utilized...
In the process of software development, the most important phase is to select a software development model and a software process which are suit to the actual situation of an organization or a project, This paper introduces and summarizes the status and development trend of the development model based on XP method, and gives the characteristics and applicable occasions of the model.
A novel system based on cooperative distributed space-time block code (DSTBC)and multi-band orthogonal frequency division multiple (MB-OFDM) is proposed which works well on multiple single-antenna users wireless networks in ultra-wideband system. In this system, using MB-OFDM technology modulate data to subcarriers, can resist the influence of frequency selective fading channel effectively. Over cooperative...
In this paper we evaluate the performance of a multi stage receiver for coded signals (using space time block codes) when MIMO (multi input multi output) channels are employed. This provides a new paradigm for transmission over Rayleigh fading channels where scattering phenomenon is a major obstruction. At the transmitter side data encoded using a space-time block code, and the encoded data is split...
Differential turbo coded OFDM(DTC-OFDM) scheme was presented, together with a differential soft-detection method for Ka-band satellite communications. DTC-OFDM combines Turbo codes, orthogonal frequency division multiplexing (OFDM) modulation and differential detection, which has the advantages of high spectrum efficiency and suppression of multipath fading, jamming and noise. The DTC-OFDM system...
In this paper, we propose a simple hardware implementation scheme of the D-STBC system. According to the theory of D-STBC, the specific implementation scheme of encoding and decoding come up. In the design, one differential encoding table is set up to replace the complex computation of the encoder; two decoding tables are set up to replace the complex computation of the decoder. Meanwhile likelihood...
In this paper eigen-beamforming and differential space-time modulation (DSTM) are combined together to construct a robust and relatively simple system for multiple-input multiple-output (MIMO) Ricean fading channels. A transmission scheme with feedback link is developed here that combines beamforming with differential multi-antenna modulation based on orthogonal space-time block coding. The power...
With the dramatically develop Internet in businesses which have become a new medium to interact with customers, the challenges for Web site companies are how to design good Web system and interaction in order to retain customers and increase sales. However, customers' shopping behaviors on World Wide Web (WWW) are still inconclusive. In the compelling online environment, understanding how online consumers...
There are 2,565 auction Web sites on online-auction list reports. Therefore, to understand consumers intention in using online auction and royalty is a critical issue. Yet, few studies have made on users intention to use online auction. Even though extensive researches focus on online shopping intention, however, we can not consider they both are same on use intention. Because online auction is involve...
Different from terrestrial sensor networks, underwater sensor networks use acoustic channels for communication and most sensor nodes are mobile due to water current. These distinctions feature underwater sensor networks with highly dynamic topology, high bit error rate, large propagation delay, and low available bandwidth. Traditional ARQ series are not suitable due to their frequent feedbacks, which...
This paper proposes a new packet marking algorithm which is based on the path identification of autonomous system (AS). The algorithm mainly marks the packets with AS numbers through border gateway protocol (BGP) routers. According to the marked information in the packets, victims can not only reconstruct the AS path that the attack packets have passed by and trace the attack source to the original...
In this paper, we propose an efficient rate one quasi-orthogonal space-time block code for three antenna system. In order to compensate the performance degradation due to quasi-orthogonal scheme, in this proposed scheme, we incorporate a selective receiver for decoding. The receiver divides the received signals into two groups, and two receiving antennas alternatively operate to receive the divided...
The sorting and feature extraction of radar signal are important precondition of the recognition and location to the radars in reconnaissance areas, and they are also an important piece of content in radar countermeasure reconnaissance information analysis. Radar signal sorting is to separate the pulse signals of each radar from the complex signal pulse data received by radar countermeasure scout,...
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