Routing Protocol Based on Grover’s Searching Algorithm for Mobile Ad-hoc Networks

In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated with traditional routing protocols in MANETs, such as poor anti-fading performance and slow convergence rate, for basic Dynamic Source Routing (DSR), we propose a new routing model based on Grover's searching algorithm. With this new routing model, each node maintains a node vector function, and all the nodes can obtain a node probability vector using Grover's algorithm, and then select an optimal routing according to node probability. Simulation results show that compared with DSR, this new routing protocol can effectively extend the network lifetime, as well as reduce the network delay and the number of routing hops. It can also significantly improve the anti-jamming capability of the network.

A Control Mechanism of Stream Media Based on 3G Network

In this paper, we use RTP/RTCP over unreliable UDP to realize the transportation of real time streaming. Meanwhile, according to the transmission feedback and network parameters, we analyze and calculate the network delay, packet loss and RTT (round trip time) to determine the network state. Finally, we propose a streaming media transmission ??control scheme which could sense the network state and quickly adjust the rate of the sending side. It takes congestion, packet loss rate into comprehensive consideration and improves the overall performance of 3G network stream media.

Time-Domain Traveling Wave Model of Single-Section Quantum Dot Mode-Locked Lasers with Optical Feedback

The optical feedback modulations of a passively mode-locked semiconductor laser with quantum dot structure were investigated in this study. The delay-induced dynamics of QD MLL under the condition of optical feedback have been studied by exploiting a time domain traveling wave(TDTW) model. The conventional TDTW model was improved to make it suitable for studying optical feedback system, especially the system with long external cavity structure. Combing the TDTW model with optical feedback and carrier rate equations, the pulse variation of a single section QD MLL was studied. This new model shows good agreement with the published experimental data. The roundtrip time and local light intensity modulation to the pulse evolution of QD MLL were studied. The results show that when the time for a light to go to and return from external cavity is equal to the integral times of the period of laser pulse without external feedback, resonance will be formed, and the period of pulse sequence is the shortest. The results also show that the stronger the local light intensity modulation is, the shorter the pulse period is.

Physical Properties of the Zn_xCd_1-xSe Alloys: Ab-Initio Method

The present work performs self-consistent ab initio full-potential linear muffin-tin orbital (FP-LMTO) method to study the structural and electronic properties of the ternary ZnxCd1-xSe alloy, based on density functional theory (DFT). In this approach, both the local density approximation (LDA) and the generalized gradient approximation (GGA) were used for the exchange-correlation potential calculation. The ground-state properties are determined for the bulk materials CdSe, ZnSe and their alloy in cubic phase. In particular, the lattice constant, bulk modulus, electronic band structures and effective mass. We mainly showed deviation of the lattice parameter and bulk modulus from Vegard’s law of our alloys. We also presented the microscopic origins of the gap bowing using the approach of Zunger et al. The results are compared with other theoretical calculations and experimental data and are in reasonable agreement.

<i>Ab Initio</i>Study of Structural and Electronic Properties of Barium Chalcogenide Alloys

First-principles calculations have been used to study the structural and electronic properties of BaS1–xSex ternary alloy using full-potential muffin-tin orbital’s (FP-LMTO) method within density functional theory (DFT). In this approach, the local-density approximation (LDA) and generalized gradient approximation (GGA) are used for the exchange-correlation (XC) potential. The effect of composition on lattice parameter, bulk modulus, band gap and effective mass was investigated. The deviations of the lattice constant from Vegard’s law and the bulk modulus from linear concentration depend- ence were observed for BaS1–xSex alloy. The microscopic origins of bowing parameter were explained using approach of Zunger and co-workers. Accordance is found from the comparison of our results with other experimental and theo- retical calculations.

Non-Orthogonal Transmission for User and Control Plane Split Architecture in 5G Systems and Beyond: Performance Analysis and Design Insights

In next generation networks,mobility management will be a critical issue due to dense base station(BS)deployment,for which user and control plane split architecture provides a promising solution.Jointly designing such architecture with nonorthogonal transmission brings in more flexibility to further improve system efficiency.This paper proposes a non-orthogonal transmission design for user and control plane split architecture.In this design,user equipments(UEs)will select the BS providing the strongest received signal to associate its data channel,but constantly connect its control channel to the nearest macro-cell BS(MBS).Upon non-orthogonal transmission,an MBS can multiplex data traffics and control signals on the same resource.Stochastic geometry based analysis is carried out to investigate outage probability,which extends its regular definition by jointly considering data and control channels,and then mobility-aware outage rate.Numerical results show that:1)The proposed split architecture alleviates the increase in handover rate for ultra dense networking,compared with conventional architecture.2)Non-orthogonal transmission outperforms traditional orthogonal transmission in the split architecture,because it is capable of accommodating more control channels.3)By carefully adjusting power levels,minimum outage probabilities can be reached for macrocell UEs in the proposed design.

Modular handover algorithm for 5G HetNets with comprehensive load index

Most existing handover decision system （HDS） designs are monolithic, resulting in high computational cost and unbalance of overall network. A novel modular handover algorithm with a comprehensive load index for the 5th generation （5G） heterogeneous networks （HetNets） is proposed. In this paper, the handover parameters, serving as the basis for handover, are classified into network＇s quality of service （QoS） module, user preference （UP） module and degree of satisfaction （DS） module according to the new modular HDS design. To optimize switching process, the comprehensive network load index is deduced by using triangle module fusion operator. With respect to the existing handover algorithm, the simulation results indicate that the proposed algorithm can reduce the handover frequency and maintain user satisfaction at a higher level. Meanwhile, due to its block calculation, it can bring about 1.4 s execution time improvement.

Inter-operator radio interface based synchronization

The fourth generation （4G） wireless communication systems have been deployed or are soon to be deployed in many countries. However, with an .explosion of wireless mobile devices and services, there ~are still some challenges that cannot be accommodated even by the 4G, such as the spectrum crisis and inter-cell interference. Telecom operators have turned to commit themselves to share available resources, including hardware and software resources. Therefore, with the mutual infrastructure, the ＇integration＇ should be highlighted, especially in the fifth generation （5G） wireless systems that are expected to be deployed beyond 2020. The authors in the article proposed a potential cellular architecture, and discussed the inter-operator radio interface based synchronization （RIBS） for the 5G wireless communication systems. A scheme of inter-operator RIBS and typical scenarios, along with the analysis of the corresponding interference were given. Analysis of the shared parameters, signaling coordination of inter-operator RIBS and listening reference signal （RS） design for RIBS were also carried out.