{"title":"Effect of Beam Steering on the Performance of Misaligned Multi-Mode OAM Communications","authors":"Rui Chen, Minqiang Zou, Jiandong Li","doi":"10.1109/VTCFall.2019.8891167","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891167","url":null,"abstract":"Orbital angular momentum (OAM) at radio frequency (RF) provides a novel approach of multiplexing a set of orthogonal modes on the same frequency channel to achieve high spectral efficiencies. However, OAM communication system requires perfect alignment of the transmit and the receive antennas and this harsh precondition greatly challenges practical application of OAM mode multiplexing gain. In this paper, we first investigate the effect of non- parallel misalignment on the inter-mode interference of the RF-OAM communication system equipped with uniform circular array (UCA). Then, large-scale system analysis shows that increasing the number of antennas has little effect on the inter-mode interference induced by oblique angle, but beam steering approach could eliminate the inter-mode interference completely. Numerical simulations validate our conclusion on the effect of beam steering.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"146 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77025606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Newton-Like Adaptive Blind Decision Feedback Equalization Scheme","authors":"Wei‐Chieh Chang, Jenq-Tay Yuan","doi":"10.1109/VTCFall.2019.8891172","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891172","url":null,"abstract":"The paper aims to give considerable insights into how the use of the well-known second-order Newton method along with a whitening filter may help adaptive blind decision feedback equalizer (DFE) achieve excellent performances. Our analytical and simulation results confirmed that the proposed Newton-like adaptive blind DFE scheme significantly outperformed the ex-isting adaptive blind DFE scheme in terms of both the symbol error rate (SER) and the mean- squared error (MSE) perfor-mances.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"75 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77199418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Group Based Spreading and Symbol Puncturing Design for NOMA Systems","authors":"Chanho Yoon, Young-Jo Ko, Taejoon Kim","doi":"10.1109/VTCFall.2019.8891194","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891194","url":null,"abstract":"In this paper, we propose a flexible group-based signature shared access (GSSA) NOMA transmission scheme that spreading length and number of maximum multiplexed users are parameterized. Because the SINR is in an in-direct relationship with the increasing number of multiplexed users, we show that combination of symbol puncturing at the transmitter and ML-DF at the receiver can be an effective solution to lower both BLER and receiver complexity for handling large number of multiplexed uplink users. The proposed NOMA design for IIoT uplink offers a good trade-off point between higher spectral efficiency and high performance (reliability) with low complex multi-user iterative receiver.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"32 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81300294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geng Sun, Xiaohui Zhao, Shuang Liang, Yanheng Liu, Ying Zhang, Victor C. M. Leung
{"title":"A Hybrid Optimization Approach for Suppressing Sidelobe Level and Reducing Transmission Power in Collaborative Beamforming","authors":"Geng Sun, Xiaohui Zhao, Shuang Liang, Yanheng Liu, Ying Zhang, Victor C. M. Leung","doi":"10.1109/VTCFall.2019.8891325","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891325","url":null,"abstract":"Conventional collaborative beamforming with virtual node antenna array often results in high maximum sidelobe level (SLL) due to the unexpected node positions. In this paper, a hybrid optimization approach (HOA) for the SLL suppression and transmission power reduction is proposed. The proposed HOA organizes the node locations according to the concentric circular antenna array for location optimization. Then, a novel algorithm called variation particle chicken swarm optimization (VPCSO) is proposed to further optimize the transmission power weight of the selected array nodes. Simulations are conducted and the results show that the proposed location optimization approach is effective, and the maximum SLL of the beam patterns obtained by VPCSO is lower than that of other algorithms. Moreover, the overall transmission power weights obtained by the proposed VPCSO is the lowest among all the comparison methods.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"10 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82121518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Blind Deconvolution Meets Phase Retrieval in Optical Wireless Communications","authors":"Min Fu, Yuanming Shi","doi":"10.1109/VTCFall.2019.8891314","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891314","url":null,"abstract":"Optical wireless communication becomes a key enabling technology for achieving ultra-high data rate requirements in beyond 5G systems. In this paper, to reduce both channel signaling overhead and hardware cost in optical wireless communications, we present a blind deconvolutional phase retrieval approach to recover the source signals from phaseless measurements without a priori channel information. To deal with the coupled challenges of phaseless measurements and bilinear signaling model, we recast the signal recovery problem into a rank-one matrices recovery problem via matrix lifting, followed by relaxing each phaseless matrix measurement into its convex hull. We further propose a difference-of-convex-functions (DC) programming algorithm to solve the low-rank matrix optimization problem. This is achieved by proposing the DC representation for the rank function based on the convex Ky Fan k-norm, thereby exactly detecting the fixed-rank constraints. The numerical results demonstrate that the proposed DC approach outperforms the state-of-the-art methods in terms of signal recovery performance and the robustness to the noise.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"32 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82393002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Non-Orthogonal Multiple Access in Cooperative UAV Networks: A Stochastic Geometry Model","authors":"Jingjing Li, Yuanwei Liu, Xingwang Li, Chao Shen, Yue Chen","doi":"10.1109/VTCFall.2019.8891479","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891479","url":null,"abstract":"In this paper, a unified framework for 3-hop unmanned aerial vehicle (UAV)-assisted non-orthogonal multiple access (NOMA) network is proposed. Aim at characterizing the performance of proposed framework, by using stochastic geometry, the analytical expressions for the outage probability of uplink/downlink transmissions are derived in closed- form for randomly deployed NOMA users. To obtain more insights of the network performance, the asymptotic analyses for the outage probability in the high signal- to-noise ratio (SNR) regime are carried out. These results reveal that for the uplink transmission, there exists an error floor due to the interference from the far user, while the performance of the far user can outperform the near one for the downlink transmission, which can be explained by the fact that the far user has a higher receiving power.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"14 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78937191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On Parallel Retransmission for Uplink Ultra-Reliable and Low Latency Communications","authors":"Te-Wei Chiang, Hung-Hsiang Liang, Sheng-Shih Wang, Shiann-Tsong Sheu","doi":"10.1109/VTCFall.2019.8891432","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891432","url":null,"abstract":"This paper introduces the concept of parallel transmission and proposes two novel retransmission schemes based on parallel transmission for uplink ultra-reliable and low latency communications. One scheme performs two transmission attempts over both dedicated and shared resources in the first transmission opportunity and the retransmission over the dedicated resource in the next one if necessary. The other scheme performs parallel retransmission over both types of resources if the initial transmission is unsuccessful. We formulate the system model to analyze the reliability and resource utilization of different retransmission schemes. Numerical results show that the proposed retransmission scheme has a higher reliability than existing ones. Moreover, one of the proposed schemes significantly uses less resource than other schemes.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"6 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78945561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Low Power Consumption Cluster Scheduling and Power Control Design for Non-Orthogonal Multiple Access Aided Down-Link IoT Networks","authors":"Furong Fang, Lin Zhang, Wenjun Chen, Jing Bian","doi":"10.1109/VTCFall.2019.8891141","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891141","url":null,"abstract":"In this paper, we study the power allocation and cluster scheduling in a downlink non-orthogonal multiple access (NOMA) network deployed with massive internet of things (IoT) devices with constraints of battery capacity. Our objective is to minimize the total transmit power while meeting the quality of service (QoS) demands for each IoT device. In the considered NOMA network, each cluster can multiplex the access of more than two IoT devices. We derive the minimum power allocated to every IoT device in each cluster with considerations of the QoS demands. Then we use the potential game model to characterize this NOMA network, and present a cluster scheduling scheme. Simulation results demonstrate that using the proposed algorithm, the consumed power is far less than the power consumed by the conventional orthogonal multiple access (OMA) scheme and the conventional NOMA scheme.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"36 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76330894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Downlink Channel Tracking for FDD Large-Scale Antenna Systems","authors":"Qi Liu, Yu Han, Fan Cao, Jie Yang, M. Matthaiou","doi":"10.1109/VTCFall.2019.8891079","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891079","url":null,"abstract":"This paper tackles the problem of channel state information acquisition in mobile frequency- division-duplex large scale antenna systems and proposes a novel low-complexity low overhead method to track time-varying channels. Given the spatial reciprocity between uplink and downlink, the frequency independent parameters are tracked from the uplink, greatly reducing the training and feedback overhead in the downlink. The uplink tracking method consists of two major modules. The first detection module works at the initial time instance to accurately estimate parameters by a comprehensive algorithm. Then, the second tracking module works at the subsequent instances to track the changes by utilizing a low-overhead algorithm as well as the parameters obtained at the previous instance. Especially, a simplified dictionary is further designed to decrease the computational complexity of the tracking module. Numerical results demonstrate that the proposed tracking method can successfully detect the newly occurred and disappeared paths, and accurately trace the changes of the time-varying channel.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"161 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75968685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haonan Xie, Jian Xiong, Lin Gui, Bing Li, Jiang-an Li
{"title":"On User Cooperative Caching by Reverse Auction","authors":"Haonan Xie, Jian Xiong, Lin Gui, Bing Li, Jiang-an Li","doi":"10.1109/VTCFall.2019.8891441","DOIUrl":"https://doi.org/10.1109/VTCFall.2019.8891441","url":null,"abstract":"Caching is a very effective way to offload data traffic; and when users participate in the caching game, the costs are greatly reduced. Therefore, this paper proposes a novel scheme that user terminals (UTs) cooperatively cache popular services to the intelligent routing relay (IRR) side. We use reverse auction model to motivate UTs to collaborate and cache, since UTs are rational and selfish. In this model, IRR purchases popular services from UTs and assigns rewards to UTs. UTs use personal data traffic to obtain popular services and then cache them to the IRR side. In order to minimize UTs' waiting time while maximizing total social incomes, we use an online reverse auction strategy, first-come-first-served (FCFS) strategy to allocate winning services to UTs. Simulation results verify the effectiveness of the FCFS strategy and show that the performances of FCFS are better than those of random allocation (RA) strategy in terms of incomes, completion rate and user waiting time. Experimental results further verify the authenticity, feasibility and the efficiency of the proposed scheme.","PeriodicalId":6713,"journal":{"name":"2019 IEEE 90th Vehicular Technology Conference (VTC2019-Fall)","volume":"9 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76247933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}