Engr., Ph.D. Candidate

Telecommunication network engineer, 3G/4G radio access network researcher, innovative IT business start-up enthusiast.

Richard Afolabi is currently working as Research Assistant while completing his Ph.D at the Communication and Sensor Networks Lab at Gwangju Institute of Science and Technology, (GIST), South Korea where he also completed his MSc. Degree in Communications Systems Engineering (2007). He received his BSc. in Computer Science from The University of Ibadan, Nigeria, in 2004.

His current research interests span network resource allocation and optimization, MBMS / multicasting techniques, cognitive radio and wireless relay networks both in WiMAX and LTE. He actively serves as technical reviewer for various conferences and journals including Vehicular Tech. Conference (VTC), IEEE Trans. on Vehicular Tech. (TVT), IEEE Communication Letters among others.

Publications
Scientific Contributions & Technical Publications.

Journal Publications

  1. Richard O. Afolabi, Binh V. Nguyen, Kiseon Kim, "Amortized Weighted Averaging For Multimedia Broadcast and Multicast Systems," IEEE Communications Letters. Impact Factor: 1.16     Status:   Submitted November 2013.     PDF Download Not Ready
    • Read Abstract

      We consider the inefficiencies of conventional multimedia broadcast multicast systems (MBMS) limited by the user with worst signal-to-noise-ratio (SNR) and we present a novel technique based on amortized weighted averaging (AWG) of individual user’s SNR. We model the system using ordered statistics of exponential and uniform distribution and derive statistics for the probability distribution function.We then apply the modelling results to study the performance of wireless multicast systems over Rayleigh fading channels. More specifically, we obtain the outage probability and reliability function for broadcast and multicast systems. Finally we compare our proposed scheme with the conventional multicast scheme. Numerical results show that the proposed AWG scheme is more reliable and significantly reduces service outage than the conventional multicasting. Click to Close
  1. Richard O. Afolabi, Binh V. Nguyen, Kiseon Kim, "Time-Efficient Resource Allocation for Single Rate OFDMA-Based Multicast Systems," IEEE Communications Letters. Impact Factor: 1.16     Status:   Submitted October 2013.     PDF Download Not Ready
    • Read Abstract

      This letter studies multicast dynamic resource allocation (MDRA) for single rate multicast group transmissionin OFDMA-based cellular systems where the base station (BS) simultaneously serves multiple multicast groups. Due to the undesirable complexity of the optimal resource allocation solution, we reformulated the problem into convex optimization to obtain bounds on the original problem. We then propose a computation time-efficient resource allocation technique (TERA) based on convexification and linearization of the original problem. Simulation results confirm that TERA can efficiently achieve nearoptimal spectral efficiency with increasing number of groups and drastically reduce overall computation time to a fraction of time taken by other algorithms. Click to Close
  1. Binh V. Nguyen, Richard O. Afolabi, Kiseon Kim, "Dependence of Outage Probability of Cooperative Systems with Single Relay Selection on Channel Correlation," IEEE Communications Letters. Impact Factor: 1.16     Status:   Accepted August 2013.     Download PDF
    • Read Abstract

      The relay selection method is a promising technique for improving the performance of cooperative systems. Most of the existing studies assume that wireless channels are statistically independent. However, in practical systems, channel correlation is more likely to be non-negligible. In this study, we investigate the dependence of the system performance of cooperative systems with single relay selection in correlated channel environments. A very tight upper bound of the system outage probability is given as a function of the channel correlation coefficient. We show that even though the system performance is considerably degraded in the high signal-to-noise ratio (SNR) region when the channel correlation approaches 1, the system still achieves a diversity order equal to the number of available relays. This implies that the system diversity order does not depend on the channel correlation. Next, we derive an asymptotic SNR loss of the system outage probability in the case of correlated channels compared with that derived in the case of independent channels. Finally, we derive a threshold value of the channel correlation because of which the system outage probability becomes twice that in the case of no correlation. Click to Close
  1. Richard O. Afolabi, Aresh Dadlani, Kiseon Kim, "Multicast Scheduling and Resource Allocation Algorithms for OFDMA-Based Systems: A Survey," IEEE Communications Surveys & Tutorials, Vol. 15, Issue No: 1, pp. 240-254, First Quarter 2013. Impact Factor: 4.818     Status:   Published.     Download PDF
    • Read Abstract

      Multicasting is emerging as an enabling technology for multimedia transmissions over wireless networks to support several groups of users with flexible quality of service (QoS) requirements. Although multicast has huge potential to push the limits of next generation communication systems; it is however one of the most challenging issues currently being addressed. In this survey, we explain multicast group formation and various forms of group rate determination approaches. We also provide a systematic review of recent channel-aware multicast scheduling and resource allocation (MSRA) techniques proposed for downlink multicast services in OFDMA based systems. We study these enabling algorithms, evaluate their core characteristics, limitations and classify them using multidimensional matrix. We cohesively review the algorithms in terms of their throughput maximization, fairness considerations, performance complexities, multi-antenna support, optimality and simplifying assumptions. We discuss existing standards employing multicasting and further highlight some potential research opportunities in multicast systems. Click to Close
  1. Richard O. Afolabi, Aftab Ahmad, Kiseon Kim, "Security Assessments of IEEE 802.15.4 Standard Based on X.802 Framework," International Journal of Security and Networks, Vol.5, Issue:2, pp. 188-197, 2010. Status:   Published.     Download PDF
    • Read Abstract

      One such wireless technology used to deploy sensitive network services requiring low rate communication, short distance application with low power consumption is the IEEE802.15.4 Low-Rate Wireless Personal Area Networks (LR-WPAN). These network services have stringent security requirements and, irrespective of the scale of deployment, the network should be secure enough to protect users, infrastructure, network services and applications. In this paper, we focus on the security mechanisms defined in the standard; evaluating it in the light of the ITU-T recommendation X.805 security architecture for end-to-end communication. We identify and assess the security dimensions, planes and layers in IEEE802.15.4 LR-WPAN as defined in the X.805 framework. Click to Close

 


 

Conference Publications

  1. Richard O. Afolabi, Binh V. Nguyen, Kiseon Kim, "Emergency Mobile Video Surveillance Over Relay-Enhanced WiMAX Vehicular Networks," IEEE GLOBECOM 2013. Status:   Submitted March 2013.     Download PDF
    • Read Abstract

      WiMAX broadband technology can potentially provide extremely high data rates for immobile nodes but its performance drops off significantly as speed of mobile nodes increases. In this paper, we study the deployment of IEEE802.16j relays as vehicle-to-roadside (V2R) infrastructures for uplink transmission of emergency mobile video surveillance (EMVS) in WiMAX networks to mitigate the degradation effect. Simulation results in OPNET confirm that relay deployment in WiMAX vehicular network can offer almost 20% capacity gain and a possible linear increase in capacity gain especially when mobile users have low gain antenna in relay environment. Click to Close
  1. Richard O. Afolabi, Kiseon Kim, "Adaptive Resource Allocation in Multicast OFDMA Transmissions Using Scalable Amortize Factor," in Proc. 4th IEEE International Conference on Ubiquitous and Future Networks, (ICUFN'12), Puket, Thailand, pp. 255-260, July 2012. Status:   Published.     Download PDF
    • Read Abstract

      WiMAX broadband technology can potentially provide extremely high data rates for immobile nodes but its performance drops off significantly as speed of mobile nodes increases. In this paper, we study the deployment of IEEE802.16j relays as vehicle-to-roadside (V2R) infrastructures for uplink transmission of emergency mobile video surveillance (EMVS) in WiMAX networks to mitigate the degradation effect. Simulation results in OPNET confirm that relay deployment in WiMAX vehicular network can offer almost 20% capacity gain and a possible linear increase in capacity gain especially when mobile users have low gain antenna in relay environment. Click to Close
  1. Richard O. Afolabi, Kiseon Kim, Aftab Ahmad, "On Secure Spectrum Sensing in Cognitive Radio Networks Using Emitters Electromagnetic Signature," in Proc. 18th IEEE International Conference on Computer Communications and Networks, (ICCCN'09), IEEE Computer Society, San Francisco, CA, USA, pp. 255-260, Aug. 2009. Status:   Published.     Download PDF
    • Read Abstract

      As Cognitive Radio Network (CRN) emerges as an extremely promising next generation wireless technology that can ease the apparent spectrum scarcity and support novel wireless applications; they will become bigger targets for hackers. Moreover, they will also be exposed to diverse security threats especially at the physical layer (PHY) spectrum sensing module. Hence, security consideration is central in its development. Starting with overview of on-going research efforts in CR-based network security, this paper describes a PHY attacker model that exploits the adaptability and flexibility of CRN. In thwarting this attack, we propose a waveform pattern recognition scheme to identify emitters and detect camouflaging attackers by using the Electromagnetic Signature (EMS) of the transceiver. On the performance of the technique, our simulation results show that our approach is effective for spectrum monitoring, mitigating denial-of-service threats and facilitating spectral efficiency. Click to Close

 


 

Thesis & Dissertation

  1. Richard O. Afolabi "Electromagnetic Signature-Based Detection of Incumbent Emulation Attackers in Spectrum Sensing of Cognitive Radio Networks," Masters Degree Thesis, School of Information and Mechatronics, Gwangju Institute of Science and Technology, Fall, 2009. Download PDF Status:   Completed.     2-Page Abstract [PDF]
    • Read Abstract

      The radio spectrum is becoming increasingly congested everyday with emerging technologies and with increasing number of wireless devices. Considering the limited bandwidth availability, accommodating the demand for higher capacity and data rates is a challenging task requiring innovative technologies that can offer new ways of ex- ploiting the available radio spectrum. The idea of Cognitive Radios arises to be an aggressive solution to increasing spectrum utilization by introducing the notion of opportunistic spectrum access. The new approaches to spectrum usage make use of the advances in technology to implement new wireless systems that can share previously allocated spectra in such a way that the incumbents of these spectra are not affected. Additionally, the allowed use of this band by CR devices is permitted on an unlicensed basis. Read more ... » Click to Close
blog
Resource Optimization in Multimedia Multicasting
Ongoing @RichardAfolabi multicast, optimization, scheduling, QoS

Project Description

Multicasting is emerging as an enabling technology for multimedia transmissions over wireless networks to support several groups of users with flexible quality of service (QoS) requirements. Although multicast has huge potential to push the limits of next generation communication systems; it is however one of the most challenging issues currently being addressed.

Read more →

In this project, our goal is to develop 1.) an energy efficient scheduling and resource allocation scheme, 2.) effective group rate determination strategies, 3.) Optimal multicast group considering several optimization constraints. This project involves sound understanding of wireless communications, several optimization methods, proficiency in mathematical and numerical tools like Mathematica and MATLAB.

Physical Layer Security in Cognitive Radio Networks
Ongoing @RichardAfolabi cognitive radio, TV white space, spectrum sensing, physical layer security

Project Description

Since Cognitive Radio Networks (CRN) is gaining increased popularity as an extremely promising wireless technology that can alleviate the apparent spectrum scarcity and support innovative wireless applications; they will become bigger targets for hackers. Moreover, they will also be exposed to diverse security threats especially at the PHY-layer spectrum sensing module.

Read more →

Hence, security consideration is central in its development. In this project, we investigate how practical physical layer security mechanisms can be incorporated into future cognitive radio systems to mitigate against a special form of vulnerability known as Incumbent Emulation Attacks. This project involve deep understanding on digital signal processing, cognitive radio fundamentals, waveform analysis, pattern recognition and programming. This work was done in collaboration with Dr. Aftab Ahmad, Computer Science Dept, Norfolk State University, USA.

Channel Aware Routing Protocol For Smart grid applications
Past @RichardAfolabi routing, smart grid, OPNET, programming

Project Description

World economy and daily human activities strongly depends on electricity. The world is currentlyy producing and using more electricity than ever. However, the grids that deliver the electrical system is aging and under increasing stree to deliver more thus creating urgent problem. This problems can have untold effect on environment, security, and economy. A smart solution is a smart modern grid application system with Two-way communications for which routing of clean, green, reliable elctricity is critical.

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In this project, our goal is to design a channel aware routing protocol for this smart grid application. This involve modelling of smart meters, smart homes, communication powerline, intelligent sensing and measurement applications among others. The project involve sound understanding of smart grid systems, network routing, OPNET modeller and C++ programming. This work was done in collaboration with Dr. Yoohwan Kim, College of Engineering, University of Nevada, Las Vegas, USA.

resume
Education
03/2010 ~ Current
PhD in Communication Engineering
Gwangju Institute of Science & Tech. (GIST), South Korea

Member: Communication and Sensor Network Lab.
Research Assistant: Conduct and publish research papers on Next Generation (xG) mobile wireless systems.
Research Topics: Multicasting, Resource Allocation, WiMAX, Optimization, Relay Networks, Resource Scheduling, OFDMA.

09/2007 ~ 08/2009
Masters in Communication Engineering
Gwangju Institute of Science & Tech. (GIST), South Korea

Member: Communication and Sensor Network Lab.
Research Assistant: Conduct and publish research papers on Next Generation (xG) mobile wireless systems.
Research Topics: Spectrum sensing, Cognitive radios and PHY layer network security.

03/2000 ~ 08/2004
Bachelors of Computer Science
University of Ibadan (UI), Nigeria

Major: Computer Science & Software Engineering.

Work Experience
09/2009 ~ 03/2010
Video Surveillance Business Developer
WithSolution Inc., Korea Electronics Technology Institute

Utilized my entrepreneurial skills, expanded over 80% of company's client-base and business to overseas market. Helped build business and client satisfaction by producing product technical docs., catalogues, user manuals. Also managed English website maintenance.

02/2005 ~ 08/2007
Network Support Engineer
Zenith Bank PLC, Nigeria

Effectively providing IT technical support functions to staff and customers. Managing daily financial transaction and implementing special e-Fund transfer. Executing inter-department functions between Operations and Fund Transfer departments. Transparently observing and reporting daily financial transactions. .

Skills
OPNET Simulations
MATLAB, Mathematica
Numerical Optimizations
WiMAX, LTE, Relay, OFDMA
Multicasting Scheduling
WordPress, HTML+CSS, C/C++
LateX, Beamer
He is the deep sort of student with a strong drive and enthusiasm for computing. His academic record was in the top ten percent of his graduating class. Richard is also a good team mate, a good team leader and a helpful class member.- Dr. Babatunde Akinkunmi, CS Dept. Chair, UI
Richard Afolabi is a very brilliant student and enterprising person. He ranked among the best in his class in academics, sports and social activities.... He is an achiever.- Dr. Seyi Osunade, Faculty, UI

Check my recommendations on my Linkedln profile.

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