Search

This paper analyzed the differentiated requirements of different business systems for communication network in three domains including urban rail transit safety production, internal management and external services, and studied the key technologies of 5G virtual private network construction, such as 5G network slicing and multi-access edge computing. Based on 5G network slicing and multi-access edge computing technology, this paper presented a technical scheme of constructing virtual 5G private network of urban rail transit for different demand scenarios, which provided a strong support for the development of urban rail transit to convenience, efficiency and intelligence.

In order to ensure the reliability, stability and high transmission rate of fifth-generation mobile communication technology(5G), this paper proposes a hybrid check matrix construction algorithm based on iterative coding algorithm with linear coding complexity. Firstly, this paper improves the traditional iterative coding algorithm and makes it suitable for non-binary low density parity check(NB-LDPC) codes. Then it adopts backward iterative method to change the coding scheme and the structure of the check matrix so that the progressive edge growth(PEG) algorithm has a lower triangular structure and uses it as the base matrix. Finally, a QC-LDPC algorithm with a lower triangular structure is used to generate a cyclic shift matrix and a finite field coefficient matrix. At the same time, the effect of the short loop is eliminated, and an optimal check matrix is selected from the algorithm. Simulation results show that the non-binary LDPC code constructed by the hybrid construction algorithm not only has linear coding and storage complexity, but also has strong error correction capability.

Recently, operators shift to 5G non-Standalone(NSA)and tend to share radio access network(RAN).In view of the current situation, network selection technology considering frequency priority and frequency priority scheduling, which performs as the general strategy for interoperation in multi-band networking for 5G NSA RAN sharing of single anchor point,is presented in this paper. From the perspective of both 2.1G mobile operator radio access network(MORAN) and 1.8G multi-operator core network(MOCN), user reselection and handover strategy are investigated, through which the interoperation in multi-band networking is implemented.

Co-construction and sharing has become a key measure to improve the quality and reduce the cost of 5G mobile network, while the demand of traditional voice service is the basic business of 5G network construction.In this paper, the voice service solutions under different 5G networking modes are discussed, and the VoLTE voice service capability under the shared networking mode of 5G NSA access network is deeply studied. Two technical solutions, VoLTE being carried in the 4G shared anchor point plot of the contractor or in the belonging 4G plot, are proposed.

Co-construction and sharing technology is an effective means to quickly build a 5G network with wide coverage, excellent technology, low investment, good perception and good experience. This paper focuses on the technical scheme of 5G access network co-construction and sharing, studies the advantages and disadvantages of various technical schemes and applicable scenarios, and analyzes the capability and implementation scheme of NSA′s sharing to SA′s sharing, so as to ensure the future competitiveness of 5G shared network.

Constructing regional non-public network based on public network is a research hotspot of emergency communication solutions. The existing non-public network architecture defined by the 3GPP standard still has many disadvantages, such as the complexity of the protocol, the difficulty of deployment and configuration, and the poor compatibility of equipment from different manufacturers. Based on demand analysis of regional emergency communication scenarios, this paper proposes a non-public network improvement scheme based on network slice technology. While avoiding the complex perception of the core network of public network and UE to non-public network, this scheme has the advantages of strong compatibility, low deployment cost and quick and simple.

Millimeter wave technology can greatly improve the system capacity and transmission rate of cellular network, which is one of the key technologies in the next generation(5G) cellular system. With the rapid increase of network traffic requirements, the ultra-dense networking(UDN) of millimeter-wave cellular networks can effectively improve the system spectrum efficiency and wireless resource utilization. For the technical characteristics of the millimeter-wave cellular network, firstly the current research at home and abroad on millimeter-wave cellular network technology is summarized. Then，the technical feature of millimeter-wave cellular network is introduced in details and the difficulties is pointed out. Finally, this paper introduced the key technologies of millimeter-wave cellular network and gave the prospect of future developments.

With the establishment of the national emergency management department, state attaches more importance to emergency communications support after disasters. In order to solve the problem of the destruction of ground communications equipment after the disaster and the inability to guarantee normal communications, the research of quick“Sky to Ground Integrated” network building based on drone base stations has entered the planning and construction period. In order to meet the requirements of large bandwidth, low latency and low cost in the development of tethered type unmanned aerial vehicle(UAV) emergency system, based the key techniques such as large-scale antenna, edge computer and network slicing based on 5G, an emergency communication solution of tethered UAV based on 5G is put forward in this paper. The implementation architecture and key technologies of the scheme are analyzed, and the corresponding conclusion is given.

Based on the characteristics of suddenness, complexity, dynamics and lack of information of navigation accidents, UAV technology has been organically integrated with China′s navigation accident emergency rescue system, becoming a research hotspot of maritime emergency communication. The user-centered UAV base station group network breaks the traditional base-centered architecture, and selects the set of potential service sites for each user to build a dynamic base station group, so that users can make full use of the diversified gain of potential service sites within the base station group and the cooperation gain between potential service sites. In this paper, a user-centered base station group networking scheme for UAV is proposed, and the user initial access scheme suitable for ship formation scenario is designed and its performance is simulated and evaluated.

Emergency communication support requires rapid deployment, quick on-line and simplified configuration process, but the network architecture based on 3GPP standard is too large and complex to meet. Lightweight 5GC aims at referring to the standard architecture, carrying virtualization technology based on the common hardware platform, realizing the decoupling of hardware and software, controlling and forwarding the cloud core network, and reducing the business process and improving the business processing capacity through the integration and tailoring of network element functions, becoming a new solution for the emergency communication industry.Based on the application scenario of emergency communication private network, this paper analyzes the implementation architecture and key technologies of lightweight 5G core network, and explores the deployment scheme based on typical cases of emergency support.

In order to adapt to the needs of rapid deployment and convenient configuration in 5G emergency communication scene, the terminal, base station, user plane function(UPF), mobile edge computing(MEC), core control and other network devices must be simple, efficient and flexible. In order to quickly build emergency communication private network application scenario, this paper puts forward a scheme of integrated edge fusion technology and equipment implementation，which provides a highly integrated wireless access，data forwarding and edge application service ability for 5G field emergency communication，at the same time, also simplifies the complexity of equipment operations and external network requirements, and improves the service performance of the whole system.

As an important supplement to the daily communication system, the emergency support communication system plays a vital role in the event of a disaster. Aiming at the requirements of the emergency support system in the event of a disaster, this paper proposes a technical solution based on 5G network slicing. Based on the flexible network customization capabilities of 5G, the performance requirements of various scenarios of the emergency support communication system on the network are analyzed. Based on the typical emergency support communication system architecture, the implementation process of the 5G network slicing of the emergency support system is discussed to realize the priority guarantee of 5G network resources for emergency services, ensure the real-time interaction and sharing of information, and improve the scientificity and timeliness of information decision-making.

Country attaches great importance to the planning and construction of emergency communication network, especially with more attention paid to the UAV(Unmanned Aerial Vehicle) emergency communication technology research. Relative to the 4G network characteristics of the "Try best", 5G with large bandwidth, low latency and high reliability of network capacity,provides a flexible configuration space for performance of a network configuration, and will gradually become the preferred technology meet the demand of emergency communication different scenarios. UAV is proposed in this paper, based on fixed wing type 5G of emergency communication coverage solution. The solution achieves network through the integration of UAV airborne 5G base stations, combined with ground acer station auxiliary. UAV base station downlink coverage and back link budget are simulated，the results show that the proposed solution can meet the demand of remote areas and emergency communication coverage.

Network slicing is one of the hot technologies in 5G, and the flexibility and timeliness of slicing management are important issues in deployment. Based on the introduction of the creation and management mechanism of 5G network slices, this paper proposes a network slice management architecture based on the openness of 5G network capabilities, and discusses the optimization process of network slice parameters and typical application scenarios.The timeliness advantage of 5G capability opening will greatly enhance the flexibility of network slice management and ensure the user′s business experience.

In order to solve the problems of the efficient synergy between the management orchestration components required for the deployment of the edge computing business and the NFV MANO components in the telecommunications cloud, this paper firstly analyzes the division of responsibilities and interaction processes between the management orchestration components of edge computing and telecommunications cloud. Secondly, based on the deep learning method and model, a solution is given to improve the management orchestration efficiency between the virtual network elements of the telecommunications cloud and the edge computing applications. Finally, the main issues and directions in this area are prospected.

With the rapid development of 5G technology, the number and density of 5G base stations will be far higher than 4G, and the construction and maintenance of base stations will become a problem that cannot be ignored. Therefore, this paper comprehensively analyzes the 5G base station decommission situation and puts forward a 5G base station decommission cost estimation scheme based on big data. With the base station historical decommission data, the LSTM neural network is used to establish the base station decommission prediction model. Then the 5G base station decommission cost estimation model is constructed, and the cost estimation of the forecast 5G base station decommission is made. Finally, through the experimental analysis, the effectiveness of the scheme is explained and suggestions are put forward.

With the advent of 5G era, a variety of application scenarios and differentiated service requirements are emerging, which puts forward higher requirements for the ability of operators to schedule network resources and service requirements. Based on the analysis of the new features of 5G network, this paper proposes an intent-based network(IBN) management scheduling system. Combined with the network architecture of IBN, various forms of service intentions are collected and translated into the required network operation and configuration, so as to realize the rapid and automatic deployment of the network. A fast scheduling algorithm is proposed based on this system to effectively schedule tasks at multiple levels and peer levels. The simulation experiments show that the fast scheduling system based on IBN improves the task processing efficiency and reduces the task scheduling processing time, which is of great significance to the service requirement scheduling guarantee of communication scenarios such as major events.

On June 14，2018，the 3GPP plenary meeting(TSG#80) approved the freeze of the independent networking function of the fifth generation mobile communication technology standard(5G NR). Coupled with the NR standard which was completed in December 2017, 5G has completed the first phase of full function standardization, and has entered a new stage of industrial sprint. The SA function freeze not only enables the 5G NR to have the ability to deploy independently, but also brings a new end to end new architecture, enabling the intelligent development of enterprise customers and vertical industries, bringing new business models for operators and industrial partners, and opening a new era of full connection. This paper firstly introduces 5G network key technologies, such as large-scale antenna, service-oriented architecture, edge calculation and network slicing, and analyzes the process and development status of 5G commercial application on the basis of elaborating the future business model applied in the three scenarios.

Based on the parameters and characteristics of the fifth generation mobile communication(5G)system and the radio altimeter, this paper uses the antenna model and propagation model provided by the International Telecommunication Union(ITU) related proposals. Through Monte Carlo simulation, the coexistence of the 4 400～4 500 MHz band 5G system and the 4 200～4 400 MHz band radio navigation service(radio altimeter) is carried out. The results show that the 5G system does not cause harmful interference to the radio navigation service(radio altimeter) in the relevant frequency band.

Sparse code multiple access(SCMA) is a novel non-orthogonal multiple access scheme to face the future 5G communication. In allusion to the problem that sparse code multiple access(SCMA) system based on a logarithm-domain MAX-Log message passing algorithm(MPA) for multiuser detection has lower detection performance, this paper adopts a method that the message updating formula of the resource node is multiplied by a factor, which can reduce the lost messages of the original MAX-Log MPA algorithm for approximate computing the updating message of resource node. The theory and simulation results show that the improved MAX-Log MPA multiuser detection algorithm can not only maintain the low complexity of the original MAX-Log MPA algorithm, but also obtains better detection performance.