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Modeling and performance analysis of OAM-GSM millimeter-wave wireless communication systems

Qi Zhang, Xusheng Xiong, Qiang Li, Tao Han, Yi Zhong,qiqiz@hust.edu.cn,xiongxusheng@hust.edu.cn,qli_patrick@hust.edu.cn,hantao@hust.edu.cn,yzhong@hust.edu.cn

Frontiers of Information Technology & Electronic Engineering 2021, Volume 22, Issue 4,   Pages 527-547 doi: 10.1631/FITEE.2000444

Abstract: In recent years, the conventional degrees of freedom in frequency and time have been fully used. It is difficult to further improve the performance of communication systems with such degrees of freedom. , which provides a new degree of freedom for millimeter-wave (mmWave) wireless communication systems, has been recognized as a key enabling technique for future mobile communication networks. By combining OAM beams that have theoretically infinite and mutually orthogonal states with the strategy, a new OAM-GSM mmWave wireless communication system is designed in this paper. A model of the OAM-GSM system is established based on channel flip precoding. The , , and BER of the proposed OAM-GSM mmWave wireless communication system are simulated. Numerical results show that, compared with traditional GSM systems, the OAM-GSM system has more complex transmission and reception mechanisms but the and maximum achievable are increased by 80% and 54%, respectively, and the BER drops by 91.5%.

Keywords： 轨道角动量；广义空间调制；毫米波通信；信道容量；能量效率；误比特率    

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Indoor massivemultiple-inputmultiple-output channel characterization and performance evaluation Article

Jian-zhi LI, Bo AI, Rui-si HE, Qi WANG, Mi YANG, Bei ZHANG, Ke GUAN, Dan-ping HE, Zhang-dui ZHONG, Ting ZHOU, Nan LI

Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 6,   Pages 773-787 doi: 10.1631/FITEE.1700021

Abstract: We present a measurement campaign to characterize an indoor massive multiple-input multiple-output (MIMO) channel system, using a 64-element virtual linear array, a 64-element virtual planar array, and a 128-element virtual planar array. The array topologies are generated using a 3D mechanical turntable. The measurements are conducted at 2, 4, 6, 11, 15, and 22 GHz, with a large bandwidth of 200 MHz. Both line-of-sight (LOS) and non-LOS (NLOS) propagation scenarios are considered. The typical channel parameters are extracted, including path loss, shadow fading, power delay profile, and root mean square (RMS) delay spread. The frequency dependence of these channel parameters is analyzed. The correlation between shadow fading and RMS delay spread is discussed. In addition, the performance of the standard linear precoder—the matched filter, which can be used for intersymbol interference (ISI) mitigation by shortening the RMS delay spread, is investigated. Other performance measures, such as entropy capacity, Demmel condition number, and channel ellipticity, are analyzed. The measured channels, which are in a rich-scattering indoor environment, are found to achieve a performance close to that in independent and identically distributed Rayleigh channels even in an LOS scenario.

Keywords： Massive MIMO     Channel modeling     5G     Shadow fading     Delay spread     Matched filter     Entropy capacity     Condition number     Channel ellipticity    

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Ergodic secrecy capacity ofMRC/SC in single-inputmultiple-output wiretap systems with imperfect channel state information Article

Hui ZHAO, You-yu TAN, Gao-feng PAN, Yun-fei CHEN

Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 4,   Pages 578-590 doi: 10.1631/FITEE.1500430

Abstract: This paper investigates the secrecy performance of maximal ratio combining (MRC) and selection combining (SC) with imperfect channel state information (CSI) in the physical layer. In a single-input multipleoutput (SIMO) wiretap channel, a source transmits confidential messages to the destination equipped with antennas using the MRC/SC scheme to process the received multiple signals. An eavesdropper equipped with antennas also adopts the MRC/SC scheme to promote successful eavesdropping. We derive the exact and asymptotic closed-form expressions for the ergodic secrecy capacity (ESC) in two cases: (1) MRC with weighting errors, and (2) SC with outdated CSI. Moreover, two important indicators, namely high signal-to-noise ratio (SNR) slope and high SNR power offset, which govern ESC at the high SNR region, are derived. Finally, simulations are conducted to validate the accuracy of our proposed analytical models. Results indicate that ESC rises with the increase of the number of antennas and the received SNR at the destination, and fades with the increase of those at the eavesdropper. Another finding is that the high SNR slope is constant, while the high SNR power offset is correlated with the number of antennas at both the destination and the eavesdropper.

Keywords： Ergodic secrecy capacity (ESC)     Maximal ratio combining (MRC)     Weighting errors     Physical layer security     Selection combining (SC)     Single-input multiple-output (SIMO)    

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The New Consideration of the Hydropower Installed Capacity

Xiong Kaizhi,Cheng Liqin

Strategic Study of CAE 2007, Volume 9, Issue 8,   Pages 26-29

Abstract:

This paper investigates the load development of power systems, the characteristics of the hydropower, and the tremendous advantages of the hydropower in peak adjusting of power systems. Using the East China power system as an illustrative example,the inconsistencies in the calculating principle of the hydropower installed capacity and the demand of the power system are assested. A new calculating principle that minimizes the cost of the power system is proposed. The effect of the new calculating principle on the hydropower installed capacity is evaluated by using a real case. The analysis provides significant insights in calculating the installed capacity of large hydropower in China.

Keywords： hydropower     installed capacity     peak adjusting     power system    

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Non-ideal space division multiple access and its application None

Ji-ying XIANG

Frontiers of Information Technology & Electronic Engineering 2018, Volume 19, Issue 3,   Pages 357-366 doi: 10.1631/FITEE.1700827

Abstract: We study the performance of space division multiple access (SDMA) under a non-ideal engineering situation. When the SDMA channel is of high inter-layer correlation and the condition number is large, the multiple user multiple input and multiple output user equipment (MUMIMOUE) grouping should be optimized, and in some cases further dimension-reduction should be applied. As the channel measuring is always non-ideal, we use two methods, feedback mode and non-feedback mode, in terms of performance and overhead. It is proposed that the non-feedback mode is preferable even for some non-reciprocal channels. Principle analysis and test results are given.

Keywords： Fifth generation (5G)     Condition number     Channel reciprocity     Feedback mode     Non-feedback mode    

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Secrecy performance analysis of single-input multiple-output generalized- Article

Hong-jiang LEI,Imran Shafique ANSARI,Chao GAO,Yong-cai GUO,Gao-feng PAN,Khalid A. QARAQE

Frontiers of Information Technology & Electronic Engineering 2016, Volume 17, Issue 10,   Pages 1074-1084 doi: 10.1631/FITEE.1601070

Abstract: In this paper, the transmission of confidential messages through single-input multiple-output (SIMO) independent and identically generalized- ( G) fading channels is considered, where the eavesdropper overhears the transmission from the transmitter to the receiver. Both the receiver and the eavesdropper are equipped with multiple antennas, and both active and passive eavesdroppings are considered where the channel state information of the eavesdropper’s channel is or is not available at the transmitter. The secrecy performance of SIMO G systems is investigated. Analytical expressions for secrecy outage probability and average secrecy capacity of SIMO systems are derived via two different methods, in which G distribution is approximated by the Gamma and mixture Gamma distributions, respectively. Numerical results are presented and verified via the Monte-Carlo simulation.

Keywords： Physical-layer security     Generalized-K fading     Average secrecy capacity     Secrecy outage probability     Mixture Gamma distribution    

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Three Basic Laws for the Network Era and Capacity Evolution for Backbone Networks

Wei Leping

Strategic Study of CAE 2001, Volume 3, Issue 5,   Pages 12-16

Abstract:

First this paper described the great challenge from the new era and its impacts on networks and indicated the huge capacity pressure faced by networks. Then, the paper discussed implications, effects and technical limits for the three basic laws which guide network era such as Moored Law, Optical Fiber Law and Metcalfe´s Law. Finally, the paper presented capacity evolution strategies for transmission links, transport nodes and service nodes in backbone networks, respectively.

Keywords： network     capacity     backbone network    

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Carrying Capacity Assessment and Its Application in Mariculture Management

Zhang Jihong, Lin Fan and Fang Jianguang

Strategic Study of CAE 2016, Volume 18, Issue 3,   Pages 85-89 doi: 10.15302/J-SSCAE-2016.03.014

Abstract:

With the growing scale of the mariculture industry, the problem of storage overcapacity in aquaculture has caused serious damage to the aquatic environment and the aggravated the dangers of disease, which have hurt the sustainable development of this industry in the long term. So it is urgent to strengthen the research on carrying capacity and to set up the scientific and adaptive management strategies. This paper reviews the progress of research and existing problems relating to the mariculture industry’s carrying capacity for cage, shellfish, macroalgae, etc; it also points out the key technologies behind capacity evaluation, including the index system of ecological capacity assessment, the numerical model of individual growth of cultured organisms, the coupling of hydrodynamic processes and ecological models; Furthermore, this article analyzes the role of carrying capacity in determining the current population density of maricultural farms and optimizing the layout of the mariculture operations, expanding the maricultural farming space and building a new mode of maricultural farming. And then, this paper advanced three suggestions for developing a capacity evaluation system in aquaculture waters, including establishing the long-term monitoring experimental station of the offshore aquaculture structure, culture capacity assessment, setting up research initiatives for aquaculture capacity research, and identifying the layout and structural adjustment for establishing a ecosystem management strategy.

Keywords： mariculture     carrying capacity     management     model    

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Records Broken for Optical Fiber Capacity and Distance

Mitch Leslie

Engineering 2021, Volume 7, Issue 2,   Pages 139-140 doi: 10.1016/j.eng.2020.12.010

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Capacity of VoIP in IEEE 802.11 Wireless LAN

Chen Liquan,Hu Aiqun,Zhou Xueli

Strategic Study of CAE 2005, Volume 7, Issue 7,   Pages 81-85

Abstract:

Voice transmitted over wireless LAN faces serious challenge because of the fluctuation of the wireless channel. In this paper, the transmission of voice over wireless LAN is firstly analyzed. Taking collision probability into account, the stochastic analysis based on a Markov chain to calculate the upper bound number of simultaneous VoIP calls that can be supported in a single cell of an IEEE 802. llb/a/g network is proposed. The upper bound capacities of G. 711, G. 729 and G. 723.1 code transmitted over 802. llb/a/g are figured out. The simulation results from NS2 simulator have validated the analysis values.

Keywords： wireless LAN     voice over IP     capacity     Markov chain    

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Pushing the Data Capacity Limit with Lasers on Silicon

Peter Weiss

Engineering 2019, Volume 5, Issue 5,   Pages 824-825 doi: 10.1016/j.eng.2019.08.011

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Improving the Performance of OFDM Channel Estimation through Subspace Projecting and Tracking

Dong Liang,Cao Xiuying,Bi Guangguo

Strategic Study of CAE 2006, Volume 8, Issue 11,   Pages 86-93

Abstract:

The LS channel estimation of OFDM systems can be viewed as a noisy observation of the true channel frequency response, so the noise component can be compressed through subspace projecting. In this paper, the substance of the improvement of LS channel estimation is analyzed when subspace projecting is enforced, and the general framework to perform subspace projecting in the context of OFDM channel estimation is given, based on which this method is exterded to non-LS channel estimation. When signal subspace varies with time, subspace tracking should be performed to maintain a good estimation of signal subspace. At the end of this paper, a subspace tracking based parametric channel estimator is presented, and computer simulation shows that this channel estimator outperforms its nonparametric counterparts.

Keywords： OFDM     subspace     projecting     tracking     channel estimation    

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Cooperative channel assignment for VANETs based on multiagent reinforcement learning Research Articles

Yun-peng Wang, Kun-xian Zheng, Da-xin Tian, Xu-ting Duan, Jian-shan Zhou,ypwang@buaa.edu.cn,zhengkunxian@buaa.edu.cn,dtian@buaa.edu.cn,duanxuting@buaa.edu.cn

Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 7,   Pages 1047-1058 doi: 10.1631/FITEE.1900308

Abstract: (DCA) plays a key role in extending vehicular ad-hoc network capacity and mitigating congestion. However, channel assignment under vehicular direct communication scenarios faces mutual influence of large-scale nodes, the lack of centralized coordination, unknown global state information, and other challenges. To solve this problem, a multiagent (RL) based cooperative DCA (RL-CDCA) mechanism is proposed. Specifically, each vehicular node can successfully learn the proper strategies of channel selection and backoff adaptation from the real-time channel state information (CSI) using two cooperative RL models. In addition, neural networks are constructed as nonlinear Q-function approximators, which facilitates the mapping of the continuously sensed input to the mixed policy output. Nodes are driven to locally share and incorporate their individual rewards such that they can optimize their policies in a distributed collaborative manner. Simulation results show that the proposed multiagent RL-CDCA can better reduce the one-hop packet delay by no less than 73.73%, improve the packet delivery ratio by no less than 12.66% on average in a highly dense situation, and improve the fairness of the global network resource allocation.

Keywords： Vehicular ad-hoc networks     Reinforcement learning     Dynamic channel assignment     Multichannel    

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A study of uplink and downlink channel spatial characteristics in an urban micro scenario at 28 GHz

Tao Jiang, Jianhua Zhang, Pan Tang, Lei Tian,jet@bupt.edu.cn,jhzhang@bupt.edu.cn

Frontiers of Information Technology & Electronic Engineering 2021, Volume 22, Issue 4,   Pages 488-502 doi: 10.1631/FITEE.2000443

Abstract: This paper presents an empirical study of the and (AoA) in an urban micro (UMi) scenario at 28 GHz. At present, most UMi measurements are conducted in the and then the situation is inferred assuming channel reciprocity. Although the channel correlation coefficient of the and can be as high as 0.8, this does not mean that they are the same. Only a real measurement can accurately describe its channel conditions, and this is what this study does. A receiver equipped with a rotatable horn antenna is mounted at the base station and the user terminal, respectively, in simulating the and . To improve the angular resolution, we extract the multipath components (MPCs) using the space-alternating generalized expectation-maximization algorithm. Also, a spatial lobe approach is used to cluster the MPCs in the power angular spectrum. By matching MPCs with objects in the environment, we find that direct propagation and first-order reflections are dominant in line-of-sight and non-line-of-sight cases. By comparing our measurement with those in standard channel models, we verify that the AoA of clusters follows a Gaussian distribution in the and . In addition, a two-dimensional Gaussian distribution for ray AoA and power is established to reflect their correlation.

Keywords： 信道测量；毫米波；上行链路；下行链路；水平到达角    

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Channelmeasurements and models for 6G: current status and future outlook Review Articles

Jian-hua ZHANG, Pan TANG, Li YU, Tao JIANG, Lei TIAN

Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 1,   Pages 39-61 doi: 10.1631/FITEE.1900450

Abstract: With the commercialization of fifth generation networks worldwide, research into sixth generation (6G) networks has been launched to meet the demands for high data rates and low latency for future services. A wireless propagation channel is the transmission medium to transfer information between the transmitter and the receiver. Moreover, channel properties determine the ultimate performance limit of wireless communication systems. Thus, conducting channel research is a prerequisite to designing 6G wireless communication systems. In this paper, we first introduce several emerging technologies and applications for 6G, such as terahertz communication, industrial Internet of Things, space-air-ground integrated network, and machine learning, and point out the developing trends of 6G channel models. Then, we give a review of channel measurements and models for the technologies and applications. Finally, the outlook for 6G channel measurements and models is discussed.

Keywords： Channel measurements     Channel models     Sixth generation     Terahertz     Industrial Internet of Things     Space-air-ground integrated network     Machine learning    

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Title Author Date Type Operation

Modeling and performance analysis of OAM-GSM millimeter-wave wireless communication systems

Qi Zhang, Xusheng Xiong, Qiang Li, Tao Han, Yi Zhong,qiqiz@hust.edu.cn,xiongxusheng@hust.edu.cn,qli_patrick@hust.edu.cn,hantao@hust.edu.cn,yzhong@hust.edu.cn

Journal Article

Indoor massivemultiple-inputmultiple-output channel characterization and performance evaluation

Jian-zhi LI, Bo AI, Rui-si HE, Qi WANG, Mi YANG, Bei ZHANG, Ke GUAN, Dan-ping HE, Zhang-dui ZHONG, Ting ZHOU, Nan LI

Journal Article

Ergodic secrecy capacity ofMRC/SC in single-inputmultiple-output wiretap systems with imperfect channel state information

Hui ZHAO, You-yu TAN, Gao-feng PAN, Yun-fei CHEN

Journal Article

The New Consideration of the Hydropower Installed Capacity

Xiong Kaizhi,Cheng Liqin

Journal Article

Non-ideal space division multiple access and its application

Ji-ying XIANG

Journal Article

Secrecy performance analysis of single-input multiple-output generalized-

Hong-jiang LEI,Imran Shafique ANSARI,Chao GAO,Yong-cai GUO,Gao-feng PAN,Khalid A. QARAQE

Journal Article

Three Basic Laws for the Network Era and Capacity Evolution for Backbone Networks

Wei Leping

Journal Article

Carrying Capacity Assessment and Its Application in Mariculture Management

Zhang Jihong, Lin Fan and Fang Jianguang

Journal Article

Records Broken for Optical Fiber Capacity and Distance

Mitch Leslie

Journal Article

Capacity of VoIP in IEEE 802.11 Wireless LAN

Chen Liquan,Hu Aiqun,Zhou Xueli

Journal Article

Pushing the Data Capacity Limit with Lasers on Silicon

Peter Weiss

Journal Article

Improving the Performance of OFDM Channel Estimation through Subspace Projecting and Tracking

Dong Liang,Cao Xiuying,Bi Guangguo

Journal Article

Cooperative channel assignment for VANETs based on multiagent reinforcement learning

Yun-peng Wang, Kun-xian Zheng, Da-xin Tian, Xu-ting Duan, Jian-shan Zhou,ypwang@buaa.edu.cn,zhengkunxian@buaa.edu.cn,dtian@buaa.edu.cn,duanxuting@buaa.edu.cn

Journal Article

A study of uplink and downlink channel spatial characteristics in an urban micro scenario at 28 GHz

Tao Jiang, Jianhua Zhang, Pan Tang, Lei Tian,jet@bupt.edu.cn,jhzhang@bupt.edu.cn

Journal Article

Channelmeasurements and models for 6G: current status and future outlook

Jian-hua ZHANG, Pan TANG, Li YU, Tao JIANG, Lei TIAN

Journal Article