Current Issue

20 February 2021, Volume 37 Issue 2

Previous Issue    Next Issue

Topic: Mobile Communication (5G) Testing

Channel modeling and performance test method for 5G

Guiming WEI, Xiang ZHANG, Yuhang GUO, Shangbing QIAO

2021, 37(2):  15-21.  doi:10.11959/j.issn.1000-0801.2021034

Asbtract ( 465 )   HTML ( 39)   PDF (879KB) ( 578 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

With the rapid development of 5G wireless communication system, the throughput of 5G gNB and user equipment (UE) in the practical field environment is of great important.How to generate the accurate model in lab, which can represent the propogation condition in the field, has drawn great interests from both the academic and industrial communities.The channel modeling methods of 4G and 5G were introduced, and for 5G UE testing, the advantages of the multi-input multi-output (MIMO) and over-the-air (OTA) performance test solution were showed.Then, a detailed description of the OTA channel modeling principle and throughput simulation results were given in order to provide reference for related work.

Research status and prospect of MIMO OTA test methods for 5G terminals

Nan MA, Fei YU, Xiaoli YANG, Xiaodong XU, Zhi ZHANG

2021, 37(2):  22-31.  doi:10.11959/j.issn.1000-0801.2021035

Asbtract ( 379 )   HTML ( 45)   PDF (2730KB) ( 486 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

MIMO (multi-input multi-output) OTA (over-the-air) testing is an important method to evaluate the radiation performance of the antenna system, as well as an indispensable step of research ＆ development (R ＆D) and mass production stages.With the advent of the 5G mobile communication system, the introduction of millimeter wave (mmWave) and other new technologies brings new challenges to the traditional MIMO OTA test method, and meanwhile makes OTA testing the only feasible solution for testing future 5G devices.Firstly, the challenges faced by 5G OTA testing was described.Then the applicability of the 4G mobile communication system OTA test method to the 5G OTA performance test was analyzed, and how to extend the low-frequency test method to the mmWave terminal test was studied.Then the current status of 3GPP’s research on MIMO OTA testing was summarized, and the system model, test principle, and performance evaluation indexes of simple-sectored multi-probe anechoic chamber (SS-MPAC) were explained in detail.In addition, smaller setup sizes can still yield reasonable measurement accuracy was verified.Finally, future research trends were prospected.

MIMO OTA performance testing of vehicles

Lei LI, Guiming WEI, Guokai JIANG, Jiaxu FENG, Xiang WU

2021, 37(2):  32-38.  doi:10.11959/j.issn.1000-0801.2021040

Asbtract ( 269 )   HTML ( 31)   PDF (888KB) ( 322 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

Intelligent traffic system is one of promising technologies for traffic industry.Based on communication among cars, pedestrian, traffic infrastructure and cellular networks, it’s able to significantly promote on road safety and efficiency by making proper traffic instructions.How to precisely evaluate the communication performance of a whole vehicle become a hot-topic in the field.Unfortunately, there is still no solution about the setup and procedures for the OTA testing.A low-cost solution was proposed by reconstructing channel models and optimizing the existing testing system framework that referred to as multi-probe anechoic chamber.The proposed method was able to multiple the test area with limited channel emulator RF channels by introducing a low-cost digital converter.Numerical simulations indicate that the proposed method has the ability to reproduce spatial and temporal correlation features of the target channel model, which is coherent with related standards’ requirements.

5G mmWave OTA test technologies

Yunzhi LING, Yu ZHANG, Hu XU, Ting CHEN

2021, 37(2):  39-47.  doi:10.11959/j.issn.1000-0801.2021042

Asbtract ( 387 )   HTML ( 25)   PDF (2474KB) ( 271 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

Millimeter wave (mmWave) is one of the key technologies of 5G communication, 5G communication will bring revolutionary improvements in network capacity, data rate, and delay.5G testing has changed from the previous conduction type to OTA testing.The challenges and difficulties encountered in 5G mmWave large bandwidth OTA testing were analyzed, and a variety of OTA test key technologies was put forward, finally the construction of 5G mmWave OTA test platform for a large bandwidth was discussed, the radio performance testing of various devices under millimeter wave OTA was completed.

Improved cell search algorithm for 5G NR

Baojiang DONG, Chen PENG, He LU

2021, 37(2):  48-54.  doi:10.11959/j.issn.1000-0801.2021036

Asbtract ( 500 )   HTML ( 53)   PDF (702KB) ( 655 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

The era of 5G NR has higher requirements for speed, capacity and user experience.In 5G NR physical layer, cell search is an indispensable process.Cell search mainly includes primary synchronization signal (PSS) detection algorithm and secondary synchronization signal (SSS) detection algorithm.The traditional PSS detection algorithm and SSS detection algorithm can’t satisfy the basic requirements of 5G NR.In order to solve this problem, an improved PSS detection algorithm based on the traditional M-segment cross-correlation detection algorithm was proposed.When the channel environment is bad, the traditional SSS detection algorithm will also fail.The improved SSS detection algorithm proposed can solve this problem.Finally, the traditional algorithm and the improved algorithm were compared and analyzed.The simulation results show that the detection performance of the proposed algorithm is significantly improved, and the detection efficiency and overall performance are also improved.

Research and application of 5G eMBB network rate improvement based on urbans scenarios

Sheng ZHOU, Tianpu LI

2021, 37(2):  55-62.  doi:10.11959/j.issn.1000-0801.2021038

Asbtract ( 227 )   HTML ( 28)   PDF (2468KB) ( 304 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

Development research of terminal evaluation system of internet of things

Jinfeng XIE, Hanqi YAN, Bingguang DENG, Yan ZHANG

2021, 37(2):  63-70.  doi:10.11959/j.issn.1000-0801.2021037

Asbtract ( 226 )   HTML ( 25)   PDF (708KB) ( 228 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

Under the large-scale commercial application of internet of things technology, the existing terminal evaluation system can not meet the new requirements of massive, multi-type and multi-form internet of things terminal evaluation.The research on the development of evaluation system for internet of things terminal was carried out, and the suggestions and methods of evaluation system for internet of things terminal were put forward from three dimensions of foundation, application and security, combined with the development trend of testing means, so as to provide reference for future development, promote the quality of IoT terminals, ensure the good interoperability between terminals and networks, and improve the end-to-end service quality.

Research and Development

Dynamic power control scheme for C-V2X communication with channel inversion

Jieping ZHAI, Xiaolan LIU, Hailin XIAO

2021, 37(2):  71-81.  doi:10.11959/j.issn.1000-0801.2021030

Asbtract ( 196 )   HTML ( 20)   PDF (1097KB) ( 148 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

In cellular vehicle-to-everything（C-V2X）system, V2V（vehicle-to-vehicle）-based communication utilizes the spectrum resource of cellular users（CUE）to reduce the load of base stations, and thus realize partial near-field V2V communication.Although the V2V-based communication can improve the transmission rate of system, it causes co-frequency interference.To solve the problem, a dynamic power control scheme with channel inversion was proposed.In this scheme, channel inversion power control on V2V users（VUE）was performed to compensate the truncation interruption caused by limited transmission power in the non-truncated area, where the co-frequency interference between cellular users and V2V users was solved through dynamic power control.Furthermore, the optimal dual solution of objective function was obtained by Lagrange multiplier method and the optimal power allocation was carried out for cellular users and V2V users by bisection method, which met the rate requirements of all cellular users.Finally, the total transmission rate of V2V users was maximized.Numerical simulation results were shown that when the total outage probability of V2V users was 0.866, the proposed scheme was promoted by 48%.

Fusion of auto encoders and multi-modal data based video recommendation method

Qiuyang GU, Chunhua JU, Gongxing WU

2021, 37(2):  82-98.  doi:10.11959/j.issn.1000-0801.2021031

Asbtract ( 286 )   HTML ( 27)   PDF (1105KB) ( 403 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

Nowadays, the commonly used linear structure video recommendation methods have the problems of non-personalized recommendation results and low accuracy, so it is extremely urgent to develop high-precision personalized video recommendation method.A video recommendation method based on the fusion of autoencoders and multi-modal data was presented.This method fused two data including text and vision for video recommendation.To be specific, the method proposed firstly used bag of words and TF-IDF methods to describe text data, and then fused the obtained features with deep convolutional descriptors extracted from visual data, so that each video document could get a multi-modal descriptors, and constructed low-dimensional sparse representation by autoencoders.Experiments were performed on the proposed model by using three real data sets.The result shows that compared with the single-modal recommendation method, the recommendation results of the proposed method are significantly improved, and the performance is better than the reference method.

GAN-based unsupervised domain adaptive person re-identification

Shengsheng ZHENG, Haibing YIN, Xiaofeng HUANG, Tianjie ZHANG

2021, 37(2):  99-106.  doi:10.11959/j.issn.1000-0801.2021016

Asbtract ( 150 )   HTML ( 22)   PDF (1352KB) ( 328 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

Aiming at the problem that the inaccurate clustering in the unsupervised domain adaptive pedestrian re-recognition results in low network recognition accuracy, an unsupervised domain adaptive pedestrian re-recognition method based on generative confrontation network was proposed.Firstly, the CNN model was optimized by using the batch normalization layer after the pooling layer, deleting a fully connected layer and adopting the Adam optimizer.Secondly, the cluster error was analyzed and the important parameter in the cluster was decided based on minimum error rate Bayesian decision theory.Finally, the generative adversarial network was utilized to adjust the cluster.These steps effectively improved the recognition accuracy of unsupervised domain adaptive person re-identification.In the case of the source domain Market-1501 and the target domain DukeMTMC-reID, experimental results show that mAP and Rank-1 can reach 53.7% and 71.6%, respectively.

Research and application of traffic engineering algorithm based on deep learning

Daoyun HU, Jin QI, Qianchun LU, Feng LI, Hongqiang FANG

2021, 37(2):  107-114.  doi:10.11959/j.issn.1000-0801.2021027

Asbtract ( 223 )   HTML ( 20)   PDF (838KB) ( 264 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

With the development and application of 5G network, the amount of traffic in network increased rapidly, which caused the lack of bandwidth resource.In order to improve the utilization of network resource and satisfy the critical user requirement for QoS (quality of service), a novel traffic engineering algorithm based on deep learning in SDN was proposed.At last, simulation results show that the proposed algorithm not only can calculate an efficient path for service in real time, but also can improve the QoS and the utilization of network resource, as well as reduce network congestion.

Electric internet of things security framework and technologies for energy interconnection

Yiying ZHANG, Baoxian ZHOU, Haoyuan PANG, Jinping CAO, Tongjia ZHANG

2021, 37(2):  115-124.  doi:10.11959/j.issn.1000-0801.2021028

Asbtract ( 255 )   HTML ( 26)   PDF (742KB) ( 443 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

Electric internet of things platform is an important support of energy internet digital innovation service, covering all aspects of power system.There are also many new security problems: how to realize the widely trusted interconnection and reliable perception of the power internet of things, how to realize the intelligent defense and security interaction of the power system, and how to solve the data, application and key security of the power information system.These problems are important tasks to be solved in the current power internet of things.Based on the development of energy internet, the security requirements and characteristics of power internet of things were analyzed.On this basis, the security framework and protection ideas of power internet of things were put forward.Then the key security technologies of the power internet of things and its future development direction were summarized and explained.

Victimization analysis model of user network behavior based on network traffic

Shengli ZHOU, Xiaoyang XU

2021, 37(2):  125-134.  doi:10.11959/j.issn.1000-0801.2021041

Asbtract ( 239 )   HTML ( 44)   PDF (1112KB) ( 238 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

The analysis of network victimization is of great significance to the prevention and control of telecom fraud.By studying the network traffic generated by the interaction between users and websites, a victimization identification model of telecom fraud crime based on network behavior flow analysis was proposed, the association rules between different behavior characteristics were analyzed, the behavior sequence features were reconstructed, and the victimization of network behavior sequence with random forest algorithm was evaluated.Based on the network behavior data set of public security organs, the experiment proves that the model can effectively improve the recognition accuracy of network behavior victimization.

Engineering and Application

Research and design of China Telecom BSS middle platform

Zhiqiong LIU, Na CHEN, Kaikai LIU, Zhuxuan HUA

2021, 37(2):  135-143.  doi:10.11959/j.issn.1000-0801.2021005

Asbtract ( 536 )   HTML ( 48)   PDF (1025KB) ( 585 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

The new business formats, new ecosystem cooperation challenges and opportunities brought by the transformation of communication technology in the 5G and cloud network integration era of telecom operators were analyzed.Combined with the current situation of China Telecom information construction, the construction scheme of enterprise middle platform which is suitable for China Telecom was put forward.Based on the construction idea of“light portal, variant application, stable middle platform”, the construction scheme of business platform was focused on.Through introducing application layer and building the middle platform, the fast and accurate response of front-end business and market were realized.And through the case introduction, the feasibility and superiority of the scheme was verified.

Storage system of power grid enterprise based on PBFT blockchain technology

Chunyan YANG, Dongmei BIN, Xin LI

2021, 37(2):  144-153.  doi:10.11959/j.issn.1000-0801.2021023

Asbtract ( 152 )   HTML ( 24)   PDF (1277KB) ( 165 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

A blockchain technology based on practical Byzantine fault tolerance (PBFT)algorithm was proposed.First of all, the traditional practical Byzantine fault tolerant algorithm was explained.The traditional algorithm included six phases: pre-stage, demand, pre-preparation, preparation, confirmation, and response.However, traditional algorithms had the disadvantages of poor real-time performance, lack of penalty mechanisms, and high bandwidth.In response to these problems, the traditional algorithm was improved, which specifically involved the accounting node, the consensus process, and the view switching process.The feasibility of the improved algorithm was further proved by testing.Applying this algorithm to power grid enterprises, the federal reserve system was implemented by the constructedvirtual warehouse, which also reduced the consumption of inventory funds.And the efficiency of inventory management in power grid enterprises was improved.

Network telemetry technology and its application in automatic network operation and maintenance

Dongfeng MAO, Man JIA, Xiaoming HE, Zhihua LIU

2021, 37(2):  154-163.  doi:10.11959/j.issn.1000-0801.2021012

Asbtract ( 335 )   HTML ( 46)   PDF (923KB) ( 633 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

As a new data acquisition technology, network telemetry has greatly enriched the diversity of data acquisition and expanded the range of traditional OAM data acquisition, whose goal is to realize real-time global network state visibility and traffic visibility.By combining with big data and AI technology, it can reduce human intervention and improve the operation and maintenance level of network automation.Firstly, the problems and challenges faced by the current IP network operation and maintenance were analyzed, and then it was elaborated that the network telemetry technology was the key enabler to realize the automatous network operation and maintenance.On this basis, the application of network telemetry technology in the IP network automatic operation and maintenance was investigated and discussed, and the reference and guidance for the automatic operation and maintenance of large-scale IP network were provided.

Intelligent correlation method of typical business data in power communication operation management

Guilong WU, Zhimin YANG, Yu HUANG

2021, 37(2):  164-172.  doi:10.11959/j.issn.1000-0801.2021014

Asbtract ( 97 )   HTML ( 19)   PDF (4632KB) ( 116 )   Knowledge map   

Figures and Tables | References | Related Articles | Metrics

In the process of power communication operation management, various independent business data, such as trouble tickets, duty logs, maintenance tickets, and inspection records, are generated and stored.These business data provide important support for the operation management of the power communication network.At present, the statistical process of most business data is relatively independent, and there is less manual correlation in the later stage.Two typical business data of duty log and trouble ticket in power communication operation management were selected, text mining technology was used to build a machine learning model combining unsupervised recall and supervised classification, and the intelligent association method between duty log and trouble ticket was proposed.Besides, the relevant historical business data in the electric power communication operation management system was used to do the experimental verification of the intelligent association method.The results show that it can achieve positive effect.