Applied Mechanics and Materials Vols. 263-266

Abstract: Relationship between nodes in peer-to-peer overlay, currently becomes a hot topic in the field of complex network. In this paper a model of peer-to-peer overlay was purposed. And then the paper focused on figuring out the mean-shortest path length (MSPL), clustering coefficient (CC) and the degree of every node which allowed us to discover the degree distribution. The results show that the degree distribution function follows approximately power law distribution and the network possesses notable clustering and small-world properties.

Abstract: A mobile ad hoc networks (MANET) is a group of mobile wireless nodes which communicate without any fixed networking infrastructure. The nodes in an ad hoc mobile network are typically powered by batteries with a limited energy supply. For MANETs, One of the most important and challenging issues is how to conserve energy, maximizing the network lifetime.Since routing is an essential function in these networks, developing power-aware routing protocols has been an intensive research area in recent years. As a result, many power-aware routing protocols have been proposed from a variety of perspectives. In this article,we propose and analyse the model of power consumption in ad hoc network, present different power-aware metrics base on power consumption and survey some power-aware routing protocols proposed for mobile ad hoc networks.

Abstract: The integration of navigation and communication technologies can be divided into three levels: system level, terminal level and the signal level. The integration technology of satellite communication and navigation is introduced briefly at first. Then the combination of communication and navigation functions at the signal level is analyzed and researched in depth. A novel idea is proposed that pseudo-range measurement and positioning can be achieved while keeping the existing communication functions, only by adding positioning related information. Finally, application of communication and navigation signal integration is prospected.

Abstract: The analysis of the (7, 4) binary hamming coding and decoding algorithm in wireless communications with C language programming was given and the verification testing was implemented on a HD 111 communication principle platform. The theory result was in consistent with that of the experiment. It shows that (7, 4) binary hamming coding could rectify one error symbol which would emerge in the signal transmission process and the decoding is easily to be brought about.

Abstract: Base on the new media service bus of Tianjin Port, aim at the business needs and characteristics of the enterprise, through the digital content aggregation system gathers and manages multimedia resources, through cataloging、processing、storage the aggregated information processed by the content center and retrieve it as an independent source of information for other systems shared-used, Finally, through the distribution of the digital content platform, the powerful route of transmission of the new media to all-round、 three-dimensional report. This platform can distribute text, graphics, images, video and other media means on different media terminals, such as online media, mobile media, making the audience to be able to get more timely, more angles, more audio-visual and personalized communication experience, especially the mobile terminal play a particular advantage to meet user’s demand of accessing and feedback of new information anytime and anywhere.

Abstract: Many machine learning techniques were proposed to classify P2P traffic and each with reasonable successes. But in the real P2P network environment, new communities of peers often attend and old communities of peers often leave. It requires the identification methods to be capable of coping with concept drift and updating the model incrementally. In this paper, we presented a concept-adapting algorithm MCStream which was based on streaming data mining techniques to identify P2P applications in Internet traffic. The MCStream used two micro-cluster structures, potential micro-cluster structures and outlier micro-cluster structures, to classify the P2P traffic and discovered the concept drift with limited memory. Our performance studied over a number of real data which was captured at a main gateway router demonstrates the effectiveness and efficiency of our method.

Abstract: To deal with the power control problem in cognitive radio (CR) networks, in this paper, the non-cooperative power game is studied, in which each CR user distributedly and asynchronously updates its transmission power. Taking into account the different quality of service (QoS) requirements, with the objective as maximizing the average utility of each CR user under the interference power constraints of primary users, we propose a QoS-aware power control game scheme and introduce the sigmoid efficiency function related with CR user’s signal-to-noise ratio threshold and the price function. Besides, extensive simulation results are presented to show the significant performance improvement of the proposed scheme compared to the existing ones.

Abstract: By using radius of decision region, an approximate formula to estimate word error rate (WER) of Turbo-like codes is proposed. The approximate formula is simply expressed in the form of Gaussian Q function, which consists of signal to noise ratio (SNR), mathematical expectation and variance of squared radii in decision region, etc. In addition, the approximate expression can be easily extended to fading channels with negligible error of WER. Simulation results show that the deviation between the proposed formula and Monte Carlo simulation is no more than 1dB over fading channels.

Abstract: The electric carrier communication is the special communicated way of electrical power system In this paper, one kind of double CPU, the low power loss, the low cost digital multiplexer has been designed in conducted the full research to this communicated way, which is satisfied the need of the electric power correspondence transmission system , especially in sports venues. In respect of hardware designing, dual-port RAM and double CPU are adopted for coordinating work and greatly improving efficiency; dual-port RAM , which functions as a shared mailbox of double CPU, is used to store markers, pointer and coordinate the work of double CPU. This article is elaborated the digital multiplexer’s hardware and the software principle of design in detail, carries on the simulation using the monolithic integrated circuit simulator, has achieved the satisfactory effect through the debug .

Abstract: For OFDM system, we proposed a channel estimation method based on radial basis function neural network (RBFNN). The neural network with Gaussian basis function is established according to the pilot pattern, where the network parameters are obtained by training channel response of pilot subcarriers as objective values for input samples. With the established network, channel coefficients of non-pilot subcarriers can be predicted. The simulation results indicate that the proposed algorithm performs well in OFDM systems under Rayleigh multipath fading channel.