Browsing by Author "Afolabi, A. S."
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Item Comparison of Interference Reduction Schemes by Femto Base Stations to Macro Cell Users(Institute of Electronics, Information and Communication Engineers (IEICE), 2010) Tanabe, Y.; Afolabi, A. S.; Ohta, C.; Tamaki, H.; Tanaka, Y.; Yamamoto, T.; Okada, Y.In 3GPP TR25.820, three kinds of approaches, access control, bandwidth control, and power control, to reduce interference from femtocell to macrocell are examined. Further, five types of configurations as combinations of these approaches are also discussed. The relative effectiveness among these configurations are, however, not clear since they are not compared in the same scenario enough. Therefore, at the beginning in this paper, under the simple scenario where one femto-cell exists in one macro-cell, we compare Shannon capacities of the following three configurations: 1) Open Access, Co-channel, and Fixed Power, 2) CSG (Closed Subscriber Group), Dedicated Channel, and Fixed Power, 3) CSG, Co-channel, and Adaptive Transmission Power. We also investigate conditions that transmission power control is effective.Item Development and Scaled-up Simulation Of An Automated Electrical Energy Management System For Passageway Illumination(Walter de Gruyter GmbH, 2020) Odetoye, O. A.; Afolabi, A. S.; Akinola, O. A.Buildings account for much of the world’s energy consumption; thus, it is important to develop ways, not just to harness more of the energy in the universe, but also to make system of devices in buildings more energyefficient. Occupancy-based illumination is an emerging trend in energy management, but research in this field has mostly been focused on illumination of rooms and workspaces in building interiors. To the best of the authors’ knowledge, there is virtually no literature on the energy optimisation of depersonalised spaces such as passageways. This paper explores the development and evaluation of a controller-based model for illumination of passageways in buildings, where relatively-large number of depersonalized luminaires are usually found and automation might prove especially beneficial. After development, testing and scaled-up simulations, results show that occupancy-based illumination of exterior corridors and semi-covered passages in buildings is feasible, economical, has significant energy savings, and is worthy of consideration for modern buildings.Item Development of mobile and desktop applications for a fingerprint-based attendance management system.(Institute of Advanced Engineering and Science (IAES), 2021) Akinola, O. A.; Olopade, S. O.; Afolabi, A. S.Mobile application technology has been at the forefront of technological advancement in recent years. This has made life easier, and tasks that were considered herculean have been made easier and executable in a much shorter time than ever. One of such tasks is the process of taking attendance during events (such as lectures and conferences) by scribbling one’s signature and other personal details on a central register. This manual process is cumbersome and inconvenient, especially when a large number of participants are involved. To address this problem, this paper presents an automated solution in which a Java-based mobile application was developed and connected wirelessly to a central database that was created using My structured query language (MySQL) application whose task, among others, was to record attendance information. The database was connected to the backend of the web-based software program which was coded in hypertext pre-processor (PHP) programming language. Authentication was achieved through username, password, and fingerprint information. The system was deployed in a university to log students’ details, time absent, time present and cumulative attendances per month and it was realised that the system was highly effective, efficient and 5 times faster than the conventional paper-based attendance logging technique.Item Fair Partitioning of the Downlink Resources of an OFDMA-based Multi-User Multi-Tier Cellular Network Using Fractional Frequency Reuse(Maruzen Co., Ltd/Maruzen Kabushikikaisha, 2012) Afolabi, A. S.; Munkhbat, E.; Takaki, Y.; Ohta, C.; Tamaki, H.; Tanaka, Y.; Yamamoto, T.; Okada, Y.Orthogonal Frequency Division Multiple Access (OFDMA) is a leading air interface candidate for future generation cellular networks. However, if deployed in a multi-user multi-tier cellular system, it is important to fairly share radio resources such as transmission power and sub-carriers among co-tier and cross-tier users. This paper focuses on a mathematical formulation of cell inner-zone radio resource partitioning variables and considers the case of an FFR-based macrocell underlaid with femtocell. By applying an exhaustive search procedure on the developed formulation, we determine the optimal radio resource partitioning parameter values from the perspectives of macrocell user fairness and femtocell throughput maximization.Item Fair Resource Partitioning Between Cell-edge and Cell-center of FFR-based Multi-tier Wireless Access Networks(Institute of Electrical and Electronics Engineers (IEEE), 2011) Afolabi, A. S.; Munkhbat, E.; Ohta, C.; Tamaki, H.This paper addresses the problem of fair radio resource partitioning between the cell-edge and cell-center regions in the context of the downlink of a SISO-OFDMA cellular system. Although, a plethora of studies concerning OFDMAbased radio resource allocation exists, it is, however, imperative to accord special attention to the proper design of network resource partitioning variables in order to ensure fairness in cell structures in which cell-wide reuse-1 is impracticable. This work focuses on the mathematical formulation of cell-edge/cell-center radio resource partitioning variables and considers the case of an FFR-based multi-layer cellular structure comprising of femtocell underlay. By way of exhaustive search procedure, we determined the optimal radio resource partitioning parameter values from the perspective of user fairness and throughput maximization.Item Interrogating the 1968/69 Class Conflict in South-western Nigeria(The Centre for Peace and Strategic Studies, University of Ilorin, 2014) Afolabi, A. S.Although some literature on post-colonial conflict in Africa have demonstrated that the crises in Western Nigeria were caused by taxation and tax-related considerations, scholarship on inter-class relations and class formation in Africa is far from being complete. The 1968/69 resource poor peasant struggles was not only between unfledged classes with very little political self awareness, this study is also an example of class conflict or more appropriately, class clashes between representatives of an urban-oriented policy of development and what a scholar refers to as 'agrarian population.' Using primary and secondary sources, the study explores the various ways through which the bureaucrats, politicians, and the military rulers shortchanged the peasants who were derogatorily designated as 'static,' 'timeless', 'changeless' individuals and groups inhabiting a backward society and deploying anachronistic agricultural techniques in a rapidly changing modern world. This research exposes the weaknesses of early post-independent rulers' tax policies by looking at how the peasants farmers in western Nigeria contested the imposition of high taxes on their personal incomes and vigorously asserted themselves. The uniqueness of this study resides not only in its adding to recent scholarship that is trying to bring the historiography of peasants of southwestern Nigeria to the standard that obtains in other places around the world, it also recognises the need for further research to preserve the social memory of the 1968/69 Agbekoya Riots through the collection, preservation and dissemination of literature on the major stakeholders in the Riots.Item Macrocell Batch Resource Allocation for a Closed Access Femto-Macro Cellular Wireless Network(Institute of Electrical and Electronics Engineers (IEEE), 2011) Afolabi, A. S.; Ohta, C.; Tamaki, H.Femtocell is an emerging technology that promises increased network capacity and enhanced indoor coverage at a low capital and operational cost. However, macrocell network performance depreciates when macrocell users (mUEs) are located indoors with femtocell base stations (FBSs), and these users are not allowed access to the FBSs (closed access). This is a critical issue that needs to be addressed in order to successfully deploy femtocell tier over existing macrocell networks. This paper proposes a macrocell proportional fair-based batch resource allocation strategy that enables FBS to be aware of macrocell resource usage schedule. In this context, batch means multiple time-slots. The knowledge of macrocell resource usage schedule enables the FBS to effectively mitigate interference caused to mUEs in its neighborhood. We show by simulation results that our proposed cross-layer interference coordination approach significantly increases the total macrocell throughput through interference reductionItem Macrocell Batch Resource Allocation for a Co-Channel Macrocell/Femtocell Network(Institute of Electronics, Information and Communication Engineers (IEICE), 2010) Afolabi, A. S.; Ohta, C.; Tamaki, H.This research work proposes an interference mitigation strategy that adjusts the maximum transmit power of femtocell base stations so as to reduce the aggregate cross-tier interference received by nearby microcell users. Most of the existing research works considered resource allocation and interference avoidance separately but in this work, both are investigated together. A resource block allocation strategy which ensures that each user served by the microcell or femtocell base station receives a fair share of the resource blocks available in the serving cell is discussed in this work. In the case of femtocell, a non-linear optimisation model is developed to maximize the total cell throughput. The optimisation process comprises of two parts, channel allocation and power allocation which are treated separately. Simulation results show that the proposed scheme can increase considerably the average microcell throughput in an interference-prone multilayer wireless network as the case of macro-femto cellular networks.Item Modelling and Development of a Radio Resource Control and Scheduling Algorithm for Long-Term Evolution (LTE) Uplink(International Information and Engineering Technology Association, 2021) Ogunrinola, O. O.; Olaniyi, I. O.; Afolabi, A. S.; Olaniyi, G. A.; Ajeigbe, O. E.Modern radio communication services transmit signals from an earth station to a high-altitude station, space station or a space radio system via a feeder link while in Global Systems for Mobile Communication (GSM) and computer networks, the radio uplink transmit from cell phones to base station linking the network core to the communication interphase via an upstream facility. Hitherto, the Single-Carrier Frequency Division Multiple Access (SC-FDMA) has been adopted for uplink access in the Long-Term Evolution (LTE) scheme by the 3GPP. In this journal, the LTE uplink radio resource allocation is addressed as an optimization problem, where the desired solution is the mapping of the schedulable UE to schedulable Resource Blocks (RBs) that maximizes the proportional fairness metric. The particle swarm optimization (PSO) has been employed for this research. PSO is an algorithm that is very easy to implement to solve real time optimization problems and has fewer parameters to adjust when compared to other evolutionary algorithms. The proposed scheme was found to outperform the First Maximum Expansion (FME) and Recursive Maximum Expansion (RME) in terms of simulation time and fairness while maintaining the throughput.Item A Novel Co-Operative Channel Assignment Scheme for Indoor Base Stations(Global Science and Technology Forum (GSTF)., 2011) Afolabi, A. S.; Ohta, C.; Tamaki, H.Abstract—This paper presents a co-operation technique of channel assignment (CA) for indoor base stations (BSs). Indoor BSs are most of the time deployed by users in an ad-hoc manner which makes prior network planning by network operators impossible. If the same pool of radio resources (e.g channels) is used by close BSs, co-operation between these BSs is vital for resolving problems such as interference. In the proposed scheme, femtocell base station (FBS), which is a typical example of indoor BS, is considered. FBSs in close proximity exchange UE-assisted (User Equipment) measured reference power information, and based on individual position of each FBS, inter-BS interaction is used to form clusters. In each cluster, the cluster-head (CH) uses channel assignment tables to assign channel resources to cluster-members (CMs) in a distributed manner. This scheme helps to ensure that the interest of neighbor BSs is always considered whenever a BS makes use of the available network resources. Our simulation results show that co-operative CA using a cluster-based approach yields higher average user throughput than autonomous channel selection by individual BSs.Item Passive Mobile Cellular Network Infrastructure Sharing: An Analysis of Wind Loading on a Multi-Operator Telecommunication Tower(Department of Civil Engineering, University of Ilorin, Nigeria, 2017-07) Ehiagwina, F. O; Afolabi, A. S.; Fakolujo, O. A.; Kehinde, O. O.; Oseni, G. M.; Anifowose, J. J.In order to overcome challenges militating against the rapid deployment of mobile cellular infrastructure, it is technically and economically crucial for a number operators to share mobile cellular infrastructure such as power supply, base station (BTS) cabin and telecommunication tower. For an efficient tower sharing, an analysis of tower’s wind loading and the tower bending moment have to be performed. In this work, we performed wind loading analyses for a multi-operator mobile cellular network. It was verified that as the number of operators increase, the wind loading value also increases. This work further observed that as the value of the antenna tilt increases, the tower wind loading proportionately increases. However, as the wind direction deviates from the normal, the wind loading reduces slightly. Finally, for six mobile cellular network operators, with total tower height set at 55m, the bending moment at a rare wind speed of up to 67 m/s was evaluated to be. It is vital that the bending moment of the telecommunication tower be lesser than the manufacturer’s specified tower bending moment limit. The results obtained from this research can be used to tighten tower survivability criterion. It will also serve as a useful tool to mobile cellular equipment designers and installers.Item A Reinforcement Learning Approach for Interference Management in Heterogeneous Wireless Networks(Kassel University Press GmbH, 2021) Afolabi, A. S.; Ahmed, S.; Akinola, O. A.Due to the increased demand for scarce wireless bandwidth, it has become insufficient to serve the network user equipment using microcell base stations only. Network densification through the addition of low power nodes (picocell) to conventional high-power nodes addresses the bandwidth dearth issue, but unfortunately introduces unwanted interference into the network which causes a reduction in throughput. The purpose of this paper is to develop a model for controlling the interference between picocell and microcell users of a cellular network so as to increase the overall network throughput. In order to achieve this, a reinforcement learning model was developed which was used in coordinating interference in a heterogeneous network comprising microcell and picocell base stations. The learning mechanism was derived based on Q-learning, which consisted of agent, state, action, and reward. The base station was modeled as the agent, while the state represented the condition of the user equipment in terms of Signal to Interference Plus Noise Ratio. The action was represented by the transmission power level and the reward was given in terms of throughput. Simulation results showed that the trend of values of the learning rate (e.g., high to low, low to high, etc.) plays a major role in throughput performance. It was particularly shown that a multi-agent system with a normal learning rate could increase the throughput of associated user equipment by a whopping 212.5% compared to a macrocell-only scheme.Item Sensitivity Degradation and Antenna Isolation Analyses for a Multi-Operator Global Systems for Mobile Communication Base Transceiver Stations(Faculty of Engineering, University of Nigeria, Nsukka, (UNN) Nigeria., 2019) Ehiagwina, F. O.; Afolabi, A. S.; Surajudeen-Bakinde, N. T.; Fakolujo, O. A.In other to mitigate challenges associated with the expansion of Global System for Mobile Communication (GSM) systems, infrastructure sharing have been proposed and adopted by some GSM operators. When infrastructure sharing is done, there is the possibility of degradation of quality of service due to Electromagnetic Compatibility issues, interference between operators, sensitivity degradation, increasing noise floor, antenna isolation requirement issue. This paper analyses the sensitivity degradation and the effects of spatial separation on antenna isolation requirement of Base Transceiver Station (BTS) receiver for a multi-operator mobile cellular systems. The data used were extracted from standards of organisation like European Telecommunications Standards Institute (ETSI) standards and others. Antenna dimension were obtained from physical observations of BTS site. By comparison with identified metrics in the standards, we verified that the number of operators that can share infrastructure is limited by the allowable sensitivity degradation. It was noted that an antenna isolation of 70dB can be achieved for GSM 900 band antennas and when GSM 1800 band antennas are used, 90dB antenna isolation is achievable greater than the minimum recommendation of 30dB.Item Social and Economic Upheaval in Colonial Nigeria: A Study of the 1954 Ago Iwoye Riot in Ijebu Province.(Ajayi Crowther University Journal of Religious Studies (ACUJORES) Publisher: Department of Religious Studies, Ajayi Crowther University, Oyo, 2022) Afolabi, A. S.One of the negative effects of colonialism on African societies was the disruption and replacement of indigenous social and economic structures, sub-structures and super-structures with structures of global capitalism, for the purpose of easy appropriation and expropriaton of local resources for the benefit of the metropolis. Adopting the historical research method, consisting of both primary and secondary sources, this study explored the political economy of yorubaland from the inception of British colonialism upto 1960 and reviewed how the British supplanted the well tested pre-exisiting political structure of the Yoruba people with the native authority system. The study found that the introduction of the British predatory tax system in Ago-Iwoye in Yorubaland, which the people considered burdensome and unfriendly, rendered the people and thier culture vulnerable to the exploitative tendencies of British colonial machineries. It also found that the British predatory and parasitic tax demands triggered the violent resistance that erupted in Ago-Iwoye, Ijebu province in 1954. The study concluded by deconstructing the racialised arguments that taxation would always lead to societal development. In reality, if a tax system is unholy, exploitative and burdensome on a people, it has the potential, always to degenerate into disturbance, war, anarchy and other dire consequences for the polity.Item Sole Native Authority (SNA) and the People at War: A Historical Review of the 1948 Erunkoja Tax Riots in Ile-Ife, Nigeria(the Department of History, University of Texas, Austin, United States of America, 2023) Afolabi, A. S.The establishment of the British colonial administration and the introduc tion of the Indirect Rule system attracted opposition and riots in some places in Southern Nigeria. Indeed, the British decentralized despotism, the introduction of some burdensome taxation policies, and other prevalent tax related consider ations naturally engendered resistance, which manifested in protest movements, revolts and outright riots in some places in Yorubaland. The article adopts the frus tration-aggression theory. Evidence gathered from primary and secondary sources, chief among them being archival sources, interviews, and the use of extant litera ture. The paper argues that the increase in taxes after World War II had a political underpinning to the protest that led to the Erunkoja riot of 1948. Put differently, the riot was a consequence of the overbearing impact that increased taxes from the Second World War had on the peopleItem The 1968-1969 Peasant Farmers’ Struggle for Social Equity in Southwestern Nigeria.(2012) Afolabi, A. S.Item The Colonial Taxation Policy among the Yoruba of South-western Nigeria and its Implications for Socio-economic Development(The Historical Society of Nigeria, 2010) Afolabi, A. S.Although the British colonial taxation policy engendered unlimited exploitation and expropriation of capital from the periphery to the metropolis, it also brought about 'changes' and 'development' in the Yoruba speaking parts of western Nigeria. Through the British implementation of the Indirect Rule System, they deviously used taxation system to exploit the indigenous terrain massively. Thus, British capitalism left indelible impact on the entire Nigerian polity. The study found that predatory leadership, gross opportunism, insincerity and ineptitude were the bane of tax administration in Western Nigeria during the colonial era. The study concluded that the British colonial tax system was disruptive of the delicate balance between the ruler and the ruled. It brought in its wake changes that were not conducive to rapid positive growth and development; the implementation of the colonial tax system systematically halted the development of indigenous institutions, and this in turn unleashed much depravation, exploitation and flight of capital, although some minor positive changes were during the colonial periItem The Dynamics of Cattle Tax (Jangali) in Northern Provinces, 1940 -1960(Adeboye Institute for Peace and Good Governance, Redeemers University, Ede, 2022) Afolabi, A. S.Taxes are important for fiscal purposes and provision of social amenities for the citizenry in any society. One tax in Nigeria, which was used to raise revenue for government expenditure was the cattle tax (Jangali or Jingali). This paper investigates the dynamics of cattle tax (Jangali) in Northern provinces from1940 to 1960. Qualitative methodology based on historical research methods was employed for the study. Primary sources were elicited from the National Archives, Kaduna and Ibadan, while secondary materials were sourced from books, journals etc. The study showed that while the Jangali contributed to the revenue of the Northern provinces in the 1940s, there was a sharp decrease in tax by 1950. While the reason for such sharp decrease was not within the scope of this paper, the study advances the need for government to key into this form of tax as it could lead to an expansion in the finances of the country, change the financial predicament of a nation, and advance the social and economic life of the pastoralists in any society.Item The Lagos Market Women during the Inter-War Years: Revisiting the Water Rate Agitation, 1932 - 1941(The Historical Society of Nigeria, 2016) Afolabi, A. S.The involvement of women in anti-colonial movements in the twentieth century and the parts they played in the social, economic and political domains still require further investigation. This paper, based mostly on archival sources, explores women's responses to the threat of colonialism on their social status. The paper focuses on women's opposition to direct and indirect taxation, paying attention to those involved in the protests and how they were received by both the colonial authorities and the traditional leaders. Indeed, although women played significant public roles in pre-colonial times, colonialism altered their positions through economic and political disenfranchisement. British colonial government's introduction of new economic policies, which altered the economic climate led to unmitigated hardship for women resulting in their vociferous demands for justice and fair play during the inter- war years, from 1932 to 1941. The agitation became officially known as the "women palaver against taxation". The paper concludes that apart from the global economic depression, predatory leadership, gross opportunism, insincerity and ineptitude on the part of tax administrators, were responsible for the "women palaver" in colonial South-western Nigeria during the inter-war years.