Chenguang He

A design of D2D-pairing scheme on Voronoi diagram

In the hybrid network of Device-to-Device (D2D) and cellular communications, reducing the co-channel interference is always hotpot problem, in which the interference involves either the co-channel among D2D terminals or between cellular and D2D links. Lower co-channel interference can improve the link spectrum efficiency effectively. This paper focus on discussing the D2D communications under the dedicated model, which is defined for no interference existing between cellular and D2D links. We depict a D2D-paring scheme to confront the influence of co-channel interference in D2D communications by introducing the Voronoi diagram. According to the location of D2D terminals, the Voronoi diagram can be constructed and rule the D2D-paring criterion that D2D terminals establish communications link only between adjacent polygons. The interference Management algorithm is proposed, which shows that small communications range causes lower co-channel interference, especially, when the channel inversion principle is considered. More intuitive result is obtained in the simulation part. Compared the D2D-paring scheme with some introduced classic literature, both the coverage probability and link spectrum efficiency can all be enhanced obviously.

Modeling and Analysis on M-RATs Cooperation for D2D Communications

This paper presents Multiple Radio Access Technologies(M-RATs) cooperative model for Device- to-Device (D2D) communications, which depends on both the licensed and unlicensed spectrum. The notion of cooperation factor is introduced to capture and analyze the threshold constraint in cooperation scenes. This paper also derives the coverage probability and link spectrum efficiency in typical RAT, which takes into consideration of cooperation factor, density of D2D users and pathloss exponent. Moreover, the metric of cooperation gain is proposed to depict the differences between cooperation with M-RATs and aggregation of multiple spectrum, which can be proved for a decreasing function of cooperation factor. Simulation and numerical results indicate that cooperation can bring higher link spectrum efficiency than that of the non-cooperation, according with the theoretical analysis perfectly.

Analysis the energy consumption of three wireless vehicle transmission model in shadow-fading environment

With the rapid growth of data traffic, the increasing data solutions are more and more difficult to cover, as the energy consumption become the urgent problem. In this paper, considering the shadow-fading effect, we model three traditional transmission model in the wireless vehicle communication environment. The three vehicle transmit model is under the cellular, including the direct transmission model, the transmission model in vehicular cell with fixed relay nodes (FRN) and mobile relay nodes (MRN). After the expression about the relationship between the transmission power and the shadow fading effect with the vehicular penetration loss (VPL) is determined, we deduce the average transmit energy band under the outage probability (OP) set. With considering the effect of the VPL and the shadow-fading, simulation and numerical results indicate that the MRN transmission model is to do better than the other two transmission model in the same OP.

Channel Compressed Estimation Based on k-Nearest Neighbor Learning

MmWave communication is receiving tremendous interest by academia, industry, and government for 5G cellular systems. Due to the short wavelength, the millimeter wave experiences high path loss and penetration loss. Compensating for path loss will require beamforming, which is based on channel estimation. However, in the actual environment, the number of multi-path is unknown. In order to solve the problem in millimeter wave system, this paper estimates the number of multi-path by utilizing k-Nearest Neighbor learning. Then we use the OMP algorithm to estimate the channel. The simulations show that the k-Nearest Neighbor learning can get better performance of channel estimations in the mmWave MIMO communication.

Research on Beamforming Algorithm for Group Scenario in Broadband Trunking System Downlink

In recent years, broadband trunking system has attracted much attention as its high rate, which can replace narrow band trunking system in private network. Beamforming technology, developed from smart antenna technology, sending the signal precoding processing, can effectively improve the system’s energy efficiency. In this paper, the multicast beamforming algorithm based on the group user CSI is proposed to improve the energy efficiency of the system. Multi-user beamforming technology can improve the energy efficiency of BSs in group scenarios of broadband Trunking system, and guarantee the QoS of group users. The two optimization problems are both NP-hard. The paper adopts SDR, dropping some constraints in the original optimization problem, transform the original optimization problem into SDP to achieve the approximation solution. The improved algorithm guarantees the QoS of the group users by changing the priority of the user. Multi-user beamforming technology can improve the energy efficiency of base stations in group scenarios of broadband Trunking system, and guarantee the QoS of group users.

Modeling and analysis on energy consumption in vehicular crowdcell

As the rapid growth of the data traffic, the mobile cellular network is under unprecedented operation pressure. Various of small cells with relay technologies have been proposed to bypass increased data with the status of the limited base station so far. Therefore, vehicular small cell gradually are attracting the attention of the researchers. In this paper, we discuss the communication model of the vehicular user under the cellular network, including the direct transmission model in cellular network, the transmission model in vehicular small cell with fixed relay nodes (FRN) and the transmission model in vehicular crowdcell with mobile relay nodes (MRN). With considering the effect of the VPL, the paper analyzes the average energy consumption of the vehicular users in two-dimensional block environment which is subject to Rayleigh fading. Simulation and numerical results indicate that the MRN transmission model in vehicular crowdcell is significantly superior to the other two transmission model with the distance between the user and the base station under the same application.

ACO-GA Combined Algorithm for Solving Spectrum Allocation Problem in D2D Communications

D2D communication is considered to be one of the key technologies in LTE-A network even in 5G communication system. Spectrum allocation problem is an important part in the study of D2D communication. Considering the spectrum allocation problem under D2D communication scenario, this paper proposes a system model with graph theory and adopt the concept of interference weights. A novel spectrum allocation algorithm ACO-GA combined algorithm is proposed. This algorithm combines ant colony algorithm and modified genetic algorithm based on the theory of graph coloring. Simulation results show that ACO-GA combined algorithm performs superior than traditional ant colony algorithm and genetic algorithm on spectrum efficiency and interference cost.

The Requirement for Mobile Relay Nodes Under Highway Scenarios

As we access data widely in our daily life, the present situation is that there is a lot of demand for data access in the process of moving while there used to access data in the static context. Under this situation, using the mobile relay nodes (MRN) in conventional cellular communication to support auxiliary transmission communication can effectively improve the ability of data transmission in the process of mobile performance. In this paper, we discuss that under the driving on the highway scenario, with the using of mobile relay nodes, we chose the whole vehicle as the communication transfer object and the middle vehicle carry as mobile relay node (MRN). Under the condition of considering the link capacity, this paper analyzes the traffic flow with the demand of the mobile relay nodes (MRNs) and conveys a digital expression. Simulation and probability analyses indicate that for three different traffic flows, it is expounded to the change of traffic to the mobile relay nodes (MRNs) demand changes.

Performance Analysis of Routing Algorithms Based on Intelligent Optimization Algorithms in Cluster Ad Hoc Network

In this paper, a mobile cluster Ad Hoc network model is presented for scenarios with large nodes number and high mobility. Intelligent optimization algorithms perform better than traditional routing algorithms in such scenarios but papers about performance comparison of these algorithms are rare. So we pick the most widely used intelligent optimization algorithms ACO, PSO and GA and describe the routing search process of these three algorithms in detail. Then we analyze performance of them together with AODV for comparison. Simulation results show that ACO, PSO and GA algorithms perform better than AODV in average throughput, packet loss rate, success link rate and average link hop.