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The following topics are dealt with: next generation networks; next generation Internet; switching and routing for Gigabit networks; optical networking; communication hardware design; communication software; wireless and mobile communications; ubiquitous networks; and digital signal processing for communications.
An efficient anti-jamming piecewise coding based on cognitive OFDM modulation in cognitive radio network (CRN) is proposed in this paper. The optimal design methods of building piecewise code with low redundancy are presented. In cognitive OFDM, anti-jamming piecewise coding could recover the lost packets in parallel interference channels by implementing different number of parity check blocks, thus...
This paper integrates PCA method and optimized LMBP neural network into intrusion detection system. The feasibility and efficiency of the optimized algorithm are approved by utilizing the KDDCUP99 dataset, constructing suitable training samples and testing samples and using MATLAB simulation experiment. Experiment shows that the improved algorithm has obvious superiority in training times and accuracy.
Wireless Underground Sensor Networks (WUSNs) can be used to monitor a variety of conditions in both underground and above ground environments. Sensor nodes in WUSNs are usually buried underground and this posses the biggest challenge in as far as implementing WUSNs is concerned. Sensors in WUSNs are expected to communicate through dense substances such as soil or rock. This paper first discusses wave...
The existing data sampling schemes can not update ROM serial numbers of DS18B20 automatically and locate DS18B20s accurately. For these reasons above, it is difficult to replace the faulty DS18B20s immediately. To solve this problem, both I/O (Input/Output) ports number of MCU (Micro Controller Unit) and the value of temperature alarm trigger registers (TH and TL) are used to determine the storage...
Wireless sensor node based on wireless wake-up technique can not only reduce its power consumption, extend the battery's life effectively but also guarantee the transmission distance and make it easy for detection. Wireless surface acoustic wave (SAW) sensor has got widely used in many fields due to its advantage of high sensitivity, small size and low cost. To overcome the shortage of passive SAW...
An integrated low-power 3-GHz dual-modulus prescaler (DMP) divided-by-32/33 with a great tolerance to the clock-edge is presented in this paper. A novel structure of CMOS MS-DFF (master-slave D flip-flop) is used in the asynchronous part of the prescaler. The DFF based on the structure can work well in the clocks with longer clock-edge and overcome general-fast-circuit's requirement of clock-edge...
Traditional information retrieval systems have several shortcomings in common, such as delaying in information updating, costing additional host and network resources, and so on. The promise of mobile multi-agent technology is becoming highly attractive. We approach to apply the mobile multi-agent technology to information retrieval in order to build a brand-new system. Although the mobile multi-agent...
The performance reduction caused by inter-carrier interference (ICI) on orthogonal frequency division multiplexing (OFDM) systems over time-varying channels is relevant especially when large OFDM symbols are employed in order to achieve an higher throughput. In this paper we propose a design method of an equalization scheme using several full-length FFTs operating on non-overlapping windows of the...
This paper briefly presents a novel spectrum trading model for OFDMA-based cognitive radio systems. In this model, primary users are able to trade their spare subcarriers with secondary users. Specifically, each subcarrier is priced by primary users and sold to secondary users for better utilities. Also, the issues of pricing policies and market equilibrium are discussed.
A relay-aided OFDMA system model with dynamic channel switching is introduced in this paper. Specifically, this model allows each user to communicate with the base station either through direct path or relaying path. The investigated problem is formulated as maximizing system capacity with joint consideration of power distribution, subcarrier selection in direct path and subcarrier paring in relaying...
In this paper, a simple protocol of cooperative transmission is developed by combining path selection with non-orthogonal amplify-forward (NAF) for the two-user single-antenna interference channel. Three time slots are enough for the proposed protocol to ensure each pair to achieve diversity gain of two, whereas existing cooperative protocols require four time slots. Analytic results, such as outage...
A heuristic multicasting traffic grooming algorithm which can easily route and assign the wavelength for transmission, and a QoS-promoted scheme for upstream transmission in FTTx optical networks are proposed. The heuristic algorithm can achieve the traffic grooming within a short period of time for any traffic types. The QoS-promoted scheme divides incoming packets of voice, video, data service into...
We focus on the Bit Error Rate (BER) performance analysis problem of high efficient turbo codes in wireless Rician channels with low Rician factor in this paper. The structure of turbo code in 3GPP LTE standard is referred. The research is investigated in several aspects to evaluate the performance of turbo codes in Rician fading channel with low Rician K-factor, such as using different channel model,...
To meet the requirements of the network activities and take into account P2P traffic classification challenges, a promising method is to use Machine Learning (ML) techniques and identify network applications based on flow features. We present a novel P2P traffic identification approach using back propagation neural network. It is demonstrated by simulation results that our approach can identify popular...
The implementation of a high precision fractional-N divider, which is one of the components of a phase-locked loop (PLL) fractional-N frequency synthesizer for Digital Audio Broadcasting (DAB) and other modern communication systems, is presented. Unconditionally stable Δ-Σ modulators of the third order (namely MASH-1-1-1) are implemented in the frequency synthesizer and they can provide a good average...
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