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The research based on the related network broadband spectrum sensing algorithm of pn code ranging. More than the traditional spectrum sensing method based on narrow band as the research basis, through the radio-frequency head band pass filter center frequency change and implementation, therefore, not effective spectrum of broadband usage in real time tracking and perception, therefore, put forward the network broadband spectrum sensing algorithm based on pseudo code ranging. Spectrum resource usage through the main user judgment, build relevant spectrum perception model, according to theory of time serial search for pseudo code capture, until the results reached the preset threshold, enter the pn code tracking, according to the obtained phase difference sequence regulating local phase to achieve two sequences are minimum steady-state phase, implementation pseudo-code tracking, thus complete the perception of broadband spectrum and tracking. The experimental results show that the improved algorithm for network broadband spectrum perception can effectively reduce because of the negative impact of such factors as the channel fading and improve the processing speed and the reliability of perception, to provide data support to improve the utilization rate of spectrum resources, has a great advantage.

Wireless systems continue to rapidly gain popularity. This fact is extremely true for data networks in the local and personal areas. Media Access Control (MAC) layer protocols have a critical role in making a typical Mobile ad hoc network and Personal ad hoc network more reliable and efficient. Choice of MAC layer protocol and other factors including number of nodes, mobility, traffic rate and playground size dictates the performance of a particular WLAN and WPAN. The aim of this paper is to analysis the performance of mobility models in IEEE802.11 MAC and IEEE 802.15.4 ZigBee MAC using NS2.34.These mobility models are RPGM, RWM, Freeway mobility and city section mobility model. Then extraction of the simulation results based on the performance metrics to calculate a Packet Delivery Ratio, data loss, end-to-end delay and Throughput.

MaxNLMRGA (Max Network-Lifetime Multicast Routing Algorithm based on Genetic algorithm) for the NLMR (Network-Lifetime Multicast Routing) problem was presented. The genetic operators of this algorithm reduce the transmission cost and energy consumption of multicast trees, and mutation operator prolongs the network lifetime, thus accelerating the convergence speed of the algorithm. Experiment results show that the multicast tree found by this algorithm not only has the minimum transmission cost, but also has the longest network lifetime. Furthermore, this algorithm converges quickly.

Transport layer protocol, for lack of effective congestion control, made an irrational bandwidth utilization ratio between UDP and TCP. Especially for streaming media transport which is easily to cause the network congestion. TFRC (TCP-friendly rate control protocol) congestion control mechanism had solved the problem effectively. However, in the high bit error rate environment of wireless network, TFPC would mistake the bit error for congestion lost packet that degrades throughput excessively. Concerning this issue, this paper put forward a self-adaptive TFRC mechanism which distinguishes congest and bit error effectively by distinguishing parameters, and adjusts the transmission rate dynamically. Simulation result reveals that self-adaptive TFRC mechanism can use link efficiently, reduce delay variation and meet the live transmission requirement of streaming media in wireless network.

In recent years, with the infiltration of new ideas in physical education, many new teaching methods have emerged. Multimedia, network and other technologies can be used to improve the teaching methods and tools. These not only enrich the form of physical education, but also play a supporting role in technical action learning. In this paper, we analyze the innovation of physical education teaching method by using network questionnaire as a new type of data source, the result shows that physical education teaching based on learning can effectively stimulate students' interest in exercise. Meanwhile, the result of students in physical education from cognitive experience, exploring issues manner, independent learning also shows the same conclusion. On this basis, we put forward the related suggestions to improve modernization of teaching methods in physical education.

The issue of data transmission in wireless sensor networks was studied. The video data collection was chosen as the object of the study, and the quality of service (QoS) problem of video transmission was analyzed. Video applications were generally characterized by large data size and many QoS requirements, which made the transmission of video always a hard problem. In this dissertation, a cross-layer and multi-path video transmission strategy (MVTS) was presented. MVTS introduced the idea of differentiated service and multipath routing, and operated in both application layer and network layer. In application layer, different types of video frames were distinguished and marked with different tags. Then in network layer these frames were identified by the tags and MVTS forwarded them in different paths. In this way, the key frames could be sent to the sink node reliably. Simulation tests were carried out, and simulation results showed that MVTS extended the network lifetime greatly and provided better assurance for quality of video applications.

Uyghur language is an agglutinative language in which words are derived from stems (or roots) by concatenating suffixes. This property makes a large number of combinations of morphemes, and greatly increases the word-vocabulary size, causing out-of-vocabulary (OOV) and data sparseness problems for statistical models. So words are split into certain sub-word units and applied to text and speech processing applications. Proper sub-word units not only provide high coverage and smaller lexicon size, but also provide semantic and syntactic information which is necessary for downstream applications. This paper discusses a general purpose morphological analyzer tool which can split a text of words into sequence of morphemes or syllables. Uyghur morpheme segmentation is a basic part of the comprehensive effort of the Uyghur language corpus compilation. As there are no delimiters for sub-word units, a supervised method, combined with certain rules and a statistical learning algorithm, is applied for morpheme segmentation. For phonetic units like syllable and phonemes, pure rule-based methods can extract with high accuracy. Most common and proper sub-words for various applications can be the linguistic morphemes for they provide linguistic information, high coverage, low lexicon size, and easily be restored to words. As the Uyghur language is written as pronounced, phonetic alterations of speech are openly expressed in text. This property makes many surface forms for a particular morpheme. A general purpose morphological analyzer must be able to analyze and export in both standard and surface forms. So the morpho-phonetic alterations like phonetic harmony, weakening, and morphological changes are summarized and learnt from training corpus. And a statistical model based morpheme segmentation tool is trained on the corpus of aligned word-morpheme sequences, and applied to predict possible morpheme sequences. For an open test set, with word coverage of 86.8% and morpheme coverage of 98.4%, the morpheme segmentation accuracy is 97.6%. This morpheme segmentation tool can output both on the standard forms and on the surface forms without costing segmentation accuracy. Furthermore, for various basic lexical units of word, morpheme, and syllable, the statistical properties are compared as a comprehensive effort of the Uyghur language corpus compilation.

Different from others, we focus on designing jamming methods for disrupting UAVs network efficiently. The jamming problem is formulated. Then we introduce two new methods (AMN-U2C and AMN-U2U) for jamming UAVs network. Both of them adopt the idea intending to achieve maximal number of jammed receiving links. AMN-U2C method searches locations for jammer by moving jammers along the path from the point of a UAV to the center point of others. AMN-U2U method searches by shifting jammers from the point of a UAV to another UAV. Finally we simulate the jamming attack on UAVs network using AMN-U2C, AMN-U2U, TP, GA and Random methods. The result shows AMN-U2U does best at most cases.

Wireless adhoc network are self-creating, self-organizing and self-administrating. The nodes within the network are free to move thus network do not rely on the preexisting infrastructure. Due to ease in deployment of mobile adhoc network wireless network are widely used. In the wireless network topology continuously changes according to the data packets to be sent at the destination path. With this so many best results in the wireless communication in this era wireless network over took wired network. In this paper we have compared the performance of two reactive MANET routing protocols AODV and DSR by using random way point mobility model. Both share similar On-Demand behavior, but the protocol's internal mechanism leads to significant performance difference. We have analyzed the performance of protocols by network load, mobility model and type of traffic (CBR). A detailed simulation has been carried out in QUALNET 6.1. The metrics used for performance analysis are Throughput, Average end-to-end Delay and Average jitter.

In the light of the characteristics of random change that underwater sensor change by time, space and frequency, select the best relay node to improve communication quality and get the diversity gain. A new optimal relay selection method is proposed in this paper, by considering two indexes synthetically that channel gain and underwater acoustic communication long time delay to select the best relay node. Based on the best relay node and minimization of bit error rate to take optimal power allocation of source node and relay node to realize network error rate’s reduction of 1.81 dB so then improve the overall performance of the network.

The issue of data collection in wireless sensor networks was studied. In this dissertation, a mobile sink node was introduced and a track fixed data collection solution (TDCS) was proposed and realized. TDCS consisted of two phases. Firstly, a number of collection sites were selected according to the sensor distribution. And then a quantum genetic algorithm was performed to calculate the shortest loop across the sites. Simulation tests were carried out. Simulation results showed that TDCS had better performance in network throughput and energy efficiency, and it could collets more data.

In this we tend to use a plan of Subnetting for sophistication 'C' address to scale back the address area. We tend to purposed “Aggregate Variable Length Subnet Masking exploitation IP4” with the assistance of fastened Length Subnet Masking, Variable Length Subnet Masking and combination fastened length Subnet Masking. scientific discipline Addresses are at a premium, therefore we tend to minimize the whole scientific discipline usages. Here, we tend to ar operating with the Cisco Packet Tracer and introduced the management of address area and key management in IPv6 network. In unicast and multicast IPv6 networks key management is one among the key security problems. To realize secure communications in such networks reliable and competent key management theme ought to be obligatory and enforced, Whenever a brand new node is accepted to affix or leave the network, a brand new key ought to be generated and distributed to each nodes within the multicast group. Inadequately, this approach will increase the amount of keys transmitted (communication cost) of the key management, whereas variety of algorithms has been projected to handle this issue, most of them have severely affected the computation price (i.e., range of key coding, decryption, and derivation) of the key management. By concentrating on communication and computation prices, we tend to provide prominence to the chance of addressing the each prices while not having to sacrifice one for the sake of the opposite. during this paper, we tend to propose a light-weight key management theme for IPv6 networks, that is capable of reducing each communication and computation prices. The performance analysis demonstrates the potency of our projected methodology as compared with the present ones in reducing such prices, whereas at identical time maintaining each forward and backward securities.

This paper proposes a Coiflet wavelet algorithm based on FPGA to realize the real-time detection of power quality transient disturbance. As to the real-time problem of wavelet algorithm software applications, the algorithm is realized on the FPGA. When Coiflet wavelet is taken as basic functions, the effect of the detecting signal singularity is good. Because of its symmetry in the time-frequency domain the algorithm could avoid the signal distortion during decomposition and reconstruction, which is convenient for subsequent signal processing. By simulating test of several kinds of signal source, the begin-end time of signal transient disturbance is contrasted. The test results show that the method is more accurate and feasible on real-time detection of power quality transient disturbance.

In recent years, Vehicular Ad Hoc Networks (VANET) has experienced a rapid development due to the advancement of wireless communication technologies, and now emerges as a promising way to provide road safety, traffic efficiency and infotainment applications. However, it is a challenge to design a reliable and efficient Medium Access Control (MAC) protocol for VANET due to its frequent topology changes and unreliable wireless links. Cooperative communication, on the other hand, can enhance the reliability of wireless links by exploiting the broadcast nature of the wireless communication. A cooperative scheme for MAC is proposed for VANET in this paper, referred to as Cooperative Distributed TDMA (Co-DTDMA). In the Co-DTDMA, neighboring nodes utilize its idle slots for cooperatively retransmitting a packet which has failed to reach the destination. Since the cooperative retransmission is conducted in node's own idle slot, the proposed scheme does not interrupt the normal transmission. Both theoretical analysis and simulation results demonstrate that the proposed scheme greatly increases the probability of successful packet transmission and decreases the packet transmission delay.

In order to increase the node energy utilization and lengthen the lifetime of the wireless sensor network (WSN), a novel clustering node sleep scheduling algorithm based on data fusion (DFS) is proposed in this paper. DFS increases cluster head's sleep time by adapting the data fusion window, which can realize the goal of energy saving and increase the whole network's lifetime. Simulation results show that the DFS method improves the effectiveness of the network energy consumption and it has better performance on the network coverage maintenance with effectively extending the lifetime of the network．

Vehicular Ad-Hoc Network (VANET) is a new communication paradigm creating a network on wheels. QOS becomes critical in VANET because of its unique characteristics, such as high mobility, frequent disconnections, rapidly changing topology, bandwidth constraints. It necessitates the need to assess the suitability of different routing protocols in various vehicular environments. In this paper, we enhanced the default back-off method of MAC 802.11p by embedding other methods, called Binary Exponential Back-off (BEB) and Modified Back-off method (MBA).The three methods are compared and the best among these in terms of QoS parameters is selected for further analysis. Further, the resulting best back-off procedure is considered to evaluate the performance of various routing protocols AODV, OLSR and ZRP. The simulations are carried out using NS-2.Nakagami propagation model with different modulation schemes, packet size variations and vehicle densities also used. The performance is investigated in terms of throughput, packet delivery ratio, routing load and end to end delay. The objective is to determine the suitable routing protocol in realistic urban scenarios with an efficient back-off mechanism.

The error rate of error correcting codes with soft-decision-decoding rarely has a closed-form expression. Bounding techniques are widely used to evaluate the performance of maximum-likelihood decoding algorithm. But the existing bounds are not tight enough especially for a low signal-to-noise ratios region and become looser when a suboptimum decoding algorithm is used. The radius of decision region is applied to evaluate the word error rate (WER) of error correcting codes with different decoding algorithms. Simulation results show that this method can effectively evaluate the WER of different decoders with 0.05dB maximum error.

Wireless Sensor Network (WSN) has been considered as a promising method for reliably monitoring civil and military environment in hazardous or dangerous conditions. Usually, sensor webs consisting of nodes with limited power and limited wireless communications are deployed to collect useful information from the field. Due to these reasons, how to improve energy efficiency is a critical issue for WSN protocols. The Low-Energy Adaptive Clustering Hierarchy (LEACH) protocol puts forward an algorithm where sensor nodes are built into clusters to fuse data before transmitting to Base Station (BS). An improved version of LEACH, called Low-Energy Adaptive Clustering Hierarchy-centralized (LEACH-C), is presented, where the central Base Station (BS) executes the clustering to improve energy efficiency. This paper presents an improvement of LEACH-C based on power, called Low-Energy Adaptive Clustering Hierarchy-central constrained (LEACH-CC), which balances energy distribution of network by means of changing range of nodes being cluster head. Stimulation results show that LEACH-CC can improve system lifetime over its comparatives.

Mobile adhoc network is defined as multi-hop radio relaying and are capable of operating without the support of any fixed infrastructure. The absence of any central coordinator makes the routing complex as compared to cellular networks. Ad hoc wireless network consist of multi-hop wireless link with distributing routing. Self-organizing and maintenance are built properties for ad hoc wireless network. The main aim of routing in ad hoc network is to find path with minimum overheads and amendment of broken paths. Time synchronization is difficult in ad hoc wireless networks. Section 1 and section 2 alleged the brief introduction of adhoc wireless network and different routing protocols used for routing in MANET's. Section 3 depicted the characteristics of an ideal routing protocol. Section 4 portrayed some of the previous work done in MANET and last is conclusion given in section 5.

The development of the Internet provides more opportunities for the agricultural supply chain, especially the application of large data. This paper analyzes the change of the price of pork from 2004 to 2013, and analyzes the impaction of the price fluctuation on the domestic demand and the income of the farmers, and puts forward the corresponding countermeasures on the basis of the analysis. To promote the healthy and stable development of the pig industry, it should be from five aspects: first, actively encourage large-scale breeding, and do a good job of prevention and control of swine industry. The second is to encourage the development of the company added farmers' breeding form. Through large-scale pig industry companies and farmers in the form of cooperation, can enable farmers to enhance market risk resilience. Third is the establishment of production, supply, and sales integration of supply chain; Four is to make full use of the Internet to achieve the integration of the supply chain of pigs. Five is the use of international trade to maintain the healthy development of the pig industry. Pork prices in the downturn, can reduce the downward pressure on domestic pork prices through

WiMAX is broadband wireless system being used for long range wireless networking, which makes this system vulnerable to security breaches. In this paperwe present authentication scheme using ID-based signature scheme for WiMAX, which offers a certificate-less public key verification. The proposed scheme has also increased message processing throughput as it has used elliptic curve cryptosystem, sigencryption and identity based cryptography.

In the new college English teaching mode based on the network environment, multimedia network has been widely used. This new teaching mode can fully mobilize enthusiasm and subjective initiative of learners to learn English. In recent years, online classroom of English teaching has shown obvious advantages and characteristics. In this paper, the author analyzes the factors that will influence college English learning, the result of which shows that autonomous learning is an effective means for College English teaching, which will not only help to improve the students' comprehension ability but also strengthen the training of English language. At the same time, the external monitoring can promote the students to develop good study habits, and has a strong role in promoting students' autonomous learning ability.

The main aim of this work is to investigate the performance of Single Carrier Frequency Division Multiple Access (SC-FDMA) in mobile communication system. Nowadays there is increase in demand for high speed data transfer in mobile communication. Different multiple access schemes like Orthogonal Frequency Division Multiplexing (OFDM) and SC-FDM are the two important schemes of Long Term Evolution (LTE) for next generation communication. In this paper, we observe the evolution of SC-FDMA in LTE by showing bit error rate variation and PAPR ratio comparison between OFDMA system and SC-OFDMA system.

In this paper, signal vector based detection (SVD) algorithm for spatial modulation (SM) is modified to achieve a near maximum-likelihood (ML) performance and reduces the complexity compared to ML. First, the proposed low-complexity SVD (LC-SVD) algorithm orders the antenna index list based on the angle between the received vector y and the channel vector j h , and then it estimates symbol by compensating the channel attenuation with transmitting antenna index list. We can trade-off between the performance and the complexity by changing the number of the candidate transmitting antennas. The theoretical analysis and simulation results show that the LC-SVD algorithm can achieve a near-ML performance with lower complexity.

The WiFi sensor network is a new technology for The Internet of Things, it main resolve the problem of informationize, it can collect thousands of sensor information by the sensors, and transform the information by WiFi sensor network. As for the function of WiFi sensor network, it must face to huge amounts of redundant data, in order to deal with the huge data, we have to code a lot of mapping code, it was a lot of time and space.In this article, we introduce a new method for WiFi sensor network management based on runtime model instead of coding. Our method have three steps: first, construct runtime model on WiFi sensor device; second, merge the distributed runtime model; last, convert the Composite Patterns Model to Application Scenario Model. The runtime composite model will help the WiFi sensor network to deal with huge amounts of redundant data. At the end of article, we apply our method on an application of enterprise management system, the results show that our method have high feasibility and effectively.