PV cell angle optimization for energy generation-consumption matching in a solar powered cellular network

An inherent problem of solar-energy-powered-smallcell base stations (SBSs) is that the energy generation of the photovoltaic (PV) cell does not match the energy consumption of the SBS in time. In this paper, we propose to optimize the PV cell orientation angle to achieve a good match between the energy generation and consumption profiles on a daily time scale. The optimization is formulated as an integer linear programming problem. We also derive an expression for the correlation between the energy generation and consumption profiles to evaluate their general interaction independent of the exact PV cell or SBS deployment setup. The numerical evaluation of the proposed angle optimization in a business area in London in summer/winter shows that the optimal PV cell orientation in summer contradicts the conventional assumption of south facing being optimal in the northern hemisphere. Instead, a southwest orientation should be chosen in summer due to its ability to shift the energy generation peak towards the energy consumption peak in the afternoon at a SBS in central London. This is in accordance with the prediction given by our derived correlation between the solar energy generation and consumption profiles

The Four-C Framework for High Capacity Ultra-Low Latency in 5G Networks: A Review

Network latency will be a critical performance metric for the Fifth Generation (5G) networks expected to be fully rolled out in 2020 through the IMT-2020 project. The multi-user multiple-input multiple-output (MU-MIMO) technology is a key enabler for the 5G massive connectivity criterion, especially from the massive densification perspective. Naturally, it appears that 5G MU-MIMO will face a daunting task to achieve an end-to-end 1 ms ultra-low latency budget if traditional network set-ups criteria are strictly adhered to. Moreover, 5G latency will have added dimensions of scalability and flexibility compared to prior existing deployed technologies. The scalability dimension caters for meeting rapid demand as new applications evolve. While flexibility complements the scalability dimension by investigating novel non-stacked protocol architecture. The goal of this review paper is to deploy ultra-low latency reduction framework for 5G communications considering flexibility and scalability. The Four (4) C framework consisting of cost, complexity, cross-layer and computing is hereby analyzed and discussed. The Four (4) C framework discusses several emerging new technologies of software defined network (SDN), network function virtualization (NFV) and fog networking. This review paper will contribute significantly towards the future implementation of flexible and high capacity ultra-low latency 5G communications

A Universal Receiver for Uplink NOMA Systems

Given its capability in efficient radio resource sharing, non-orthogonal multiple access (NOMA) has been identified as a promising technology in 5G to improve the system capacity, user connectivity, and scheduling latency. A dozen of uplink NOMA schemes have been proposed recently and this paper considers the design of a universal receiver suitable for all potential designs of NOMA schemes. Firstly, a general turbo-like iterative receiver structure is introduced, under which, a universal expectation propagation algorithm (EPA) detector with hybrid parallel interference cancellation (PIC) is proposed (EPA in short). Link-level simulations show that the proposed EPA receiver can achieve superior block error rate (BLER) performance with implementation friendly complexity and fast convergence, and is always better than the traditional codeword level MMSE-PIC receiver for various kinds of NOMA schemes.Comment: This paper has been accepted by IEEE/CIC International Conference on Communications in China (ICCC 2018). 5 pages, 4 figure

Test bench to test protocols and algorithms for multimedia delivery

Nowadays, the study of Quality of Service (QoS) in multimedia streaming is generally carried out by simulators. However, the results of these tests are not quite real. This forces researchers to work with approximations. In this paper, we implement a test bench to test the performance and assess the protocols and algorithms for multimedia delivery. This test bench let us evaluate the network parameters performance, by manipulating the devices under controlled conditions, and allow us to identify different application cases. We can confirm that the designed test bench gives us more real measures than a simulators, which allows us to do many types of tests with low cost.Jimenez, JM.; Lloret, J.; Díaz Santos, JR.; Lacuesta Gilaberte, R. (2017). Test bench to test protocols and algorithms for multimedia delivery. En Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering. Springer Verlag. 124-134. doi:10.1007/978-3-319-49580-4_12S124134Lloret, J., Garcia, M., Atenas, M., Canovas, A.: A QoE management system to improve the IPTV network. Int. J. Commun Syst 24(1), 118–138 (2011)Garcia, M., Canovas, A., Edo, M., Lloret, J.: A QoE management system for ubiquitous IPTV devices. In: The Third International Conference on Mobile Ubiquitous Computing, Systems, Services and Technologies, UBICOMM 2009, Sliema, Malta, 11–16 October 2009Álvarez, A., Pozueco, L., Cabrero, S., García Pañeda, X., García, R., Melendi, D., Díaz Orueta, G.: Adaptive streaming: a subjective catalog to assess the performance of objective QoE metrics. Netw. Protoc. Algorithms 6(2), 123–136 (2014)Jimenez, J.M., Romero, O., Rego, A., Dilendra, A., Lloret, J.: Study of multimedia delivery over software defined networks. Netw. Protoc. Algorithms 7(4), 37–62 (2015)Recomendation UIT/T G.1010: End-user multimedia QoS categories (2001). https://www.itu.int/rec/T-REC-G.1010-200111-I/enRecomendation UIT‑R M.1079-2: Performance and quality of service requirements for International Mobile Telecommunications-2000 (IMT-2000) access networks. https://www.itu.int/dms_pubrec/itu-r/rec/m/R-REC-M.1079-2-200306-I!!PDF-E.pdfGarcia, M., Lloret, J., Edo, M., Lacuesta, R.: IPTV distribution network access system using WiMAX and WLAN technologies. In: Proceedings of the 4th Edition of the UPGRADE-CN Workshop on Use of P2P GRID and Agents for the Development of Content Networks, Munich, Germany, 11–13 June 2009Atenas, M., Sendra, S., Garcia, M., Lloret, J.: IPTV performance in IEEE 802.11 n WLANs. In: IEEE GLOBECOM Workshops 2010, Miami, USA, pp. 929–933, December 2010Cisco Systems Inc. Cisco’s Visual Networking Index Forecast Projects Nearly Half the World’s Population Will Be Connected to the Internet by 2017. http://newsroom.cisco.com/press-release-content?articleId=1197391Lu, X., Tao, S., El Zarki, M., Guérin, R.: Quality based Adaptive Video Over the Internet. Department of ESE, University of Pennsylvania, Philadelphia, PA 19104 (2003)Lee, T.K., Chai, T.Y., Ngoh, L.H., Shao, X., Teo, J.C.M., Zhou, L.: An IMS-based testbed for real-time services integration and orchestration. In: IEEE Asia-Pacific Services Computing Conference (APSCC 2009), Singapore, 7–11 December 2009Mu, M., Mauthe, A., Casson, J., Tyson, G., Garcia, F.: LA1 TestBed: evaluation testbed to assess the impact of network impairments on video quality. In: 5th International Conference on Testbeds and Research Infrastructures for the Development of Networks & Communities and Workshops (TridentCom 2009), Washington, DC, 6–8 April 2009Kuwadekar, A., Al-Begain, K.: User centric quality of experience testing for video on demand over IMS. In: First International Conference on Computational Intelligence, Communication Systems and Networks (CICSYN 2009), Indore, India, 23–25 July 2009Downline Guide, Big Buck Bunny, Sunflower version. http://bbb3d.renderfarming.net/download.htmlFFmpeg. http://www.ffmpeg.org/about.htmlSullivan, G.J., Wiegand, T.: Video compression - from concepts to the H.264/AVC standard. Proc. IEEE 93(1), 18–31 (2005)Estepa, A.J., Estepa, R., Vozmediano, J., Carrillo, P.: Dynamic VoIP codec selection on smartphones. Netw. Protoc. Algorithms 6(2), 22–37 (2014

Echo State Networks for Proactive Caching in Cloud-Based Radio Access Networks with Mobile Users

In this paper, the problem of proactive caching is studied for cloud radio access networks (CRANs). In the studied model, the baseband units (BBUs) can predict the content request distribution and mobility pattern of each user, determine which content to cache at remote radio heads and BBUs. This problem is formulated as an optimization problem which jointly incorporates backhaul and fronthaul loads and content caching. To solve this problem, an algorithm that combines the machine learning framework of echo state networks with sublinear algorithms is proposed. Using echo state networks (ESNs), the BBUs can predict each user's content request distribution and mobility pattern while having only limited information on the network's and user's state. In order to predict each user's periodic mobility pattern with minimal complexity, the memory capacity of the corresponding ESN is derived for a periodic input. This memory capacity is shown to be able to record the maximum amount of user information for the proposed ESN model. Then, a sublinear algorithm is proposed to determine which content to cache while using limited content request distribution samples. Simulation results using real data from Youku and the Beijing University of Posts and Telecommunications show that the proposed approach yields significant gains, in terms of sum effective capacity, that reach up to 27.8% and 30.7%, respectively, compared to random caching with clustering and random caching without clustering algorithm.Comment: Accepted in the IEEE Transactions on Wireless Communication