Antony Onim | Jomo Kenyatta University of Agriculture and Technology (original) (raw)

Papers by Antony Onim

Research paper thumbnail of Selection of Optimal SINR Threshold in Fractional Frequency Reuse by Comparing Otsu's and Entropy Method

SSRN Electronic Journal, 2022

Research paper thumbnail of Optimization of Base Station Location in 3G Networks using Mads and Fuzzy C-means

Network and Complex Systems, 2013

Distribution of Base Transceiver Stations (BTS) with an aim of maintaining high Quality of Servic... more Distribution of Base Transceiver Stations (BTS) with an aim of maintaining high Quality of Service and coverage is important to mobile operators. Rapid expansion of telecommunication industry results in stiff competition among service providers which in turn leads to greater focus on quality of services delivered. Increase in number of mobile phone usage has also led to unprecedented network expansion. Coupled to these challenges is rapid change in telecommunication technology from 2G to 4G in a short space of time. A combination of MADS and FUZZY C- MEANS is used to aid in planning Base Station Transceivers (BTS) location efficiently in order to curb capital and maintenance costs. Keywords: BTS placement, MADS, Fuzzy C-Means

Research paper thumbnail of Optimization of Base Station Location in 3G Networks using Fuzzy Clustering and Mesh Adaptive Direct Search

This paper addresses the problem of optimal distribution of Base Transceiver Stations (BTS) while... more This paper addresses the problem of optimal distribution of Base Transceiver Stations (BTS) while maintaining acceptable Quality of Service. Expansion of telecommunication industry results in stiff competition among service providers which leads to focus on quality of services delivered. Increase in number of mobile phone usage has also led to unprecedented increase in network traffic. This paper also shows how optimal BTS locations shift when Mobile Stations (MS) increase.

Research paper thumbnail of Fractional Frequency Reuse Optimal SINR Threshold Selection Using NIR and ISODATA

Telecom

A vital part of cellular network evolution has been long-term evolution networks. In these networ... more A vital part of cellular network evolution has been long-term evolution networks. In these networks, it is important to mitigate inter-cell interference. Fractional frequency re-use has been proposed to address this. The method involves the division of cells into two regions based on a signal-to-interference-plus-noise-ratio threshold value. The inner region adopts a frequency re-use of one (1), while the outer region uses a higher frequency re-use factor. Setting the threshold value is a critical problem addressed in this paper. The proposed approach adapts techniques used in image processing called global-thresholding techniques. The approaches considered are iterative self-organizing data analysis and native integral ratio. Mobile stations in a cell continuously report their signal-to-interference-plus-noise-ratio values to the base station. These reported values are used to determine a threshold which dictates which subscribers fall in the inner and outer regions. The threshold ...

Research paper thumbnail of Evaluation Of Different Transmission Modes In Coordinated Homogeneous And Heterogeneous Networks

LTE supports different transmission modes such as: Single Input Single Output (SISO), Transmissio... more LTE supports different transmission modes such as: Single Input Single Output (SISO), Transmission diversity (TxD) and Multiple Input Multiple Output (MIMO). TxD aims at improving the signal strength at the receiver by using two or more transmit antennas while MIMO techniques are used to increase the throughput according to the number of antennas used. Coordinated Multipoint (CoMP) techniques reduce interference and improve signal strength. Homogeneous networks consist entirely of macrocells while heterogeneous networks (HetNets) have both macrocells and femtocells. HetNets are used to meet increased mobile traffic demands by providing low power nodes closer to the user equipment. This paper reviews popular transmission modes and investigates their performance in both homogeneous and heterogenous CoMP networks. Simulation of the different transmission modes is carried out and results show that CLSM is the best transmission mode to use in in homogeneous networks, and that CLSM and OL...

Research paper thumbnail of Optimal SINR Threshold Selection In Fractional Frequency Reuse Using Otsu ’ s Method

Fractional Frequency Re-use (FFR) is a popular technique for controlling inter-cell interference ... more Fractional Frequency Re-use (FFR) is a popular technique for controlling inter-cell interference in OFDMA cellular networks. FFR involves dividing each cell into inner and outer layers, with different frequency re-use ratios for each layer. Important design parameters in FFR are the signal-tointerference-plus-noise ratio (SINR) threshold, , and the frequency allocation ratio, . In conventional FFR schemes, and are fixed and do not vary with cell conditions. A dynamic FFR scheme is developed where the optimal SINR threshold is determined using Otsu’s method, a digital image processing technique. The optimal SINR threshold is calculated based on periodic SINR values in the cells, and then set proportionately to the number of users in each layer. The designed system is evaluated through system-level simulations is found to outperform conventional FFR in terms of both throughput and fairness. Index items: LTE, FFR, Otsu’s Method, Spectral efficiency, Fairness. ——————————  —————————— Op...

Research paper thumbnail of Performance Evaluation Of Proportional Fair And Round Robin Schedulers In Two-Layer Ffr

Different fractional frequency reuse (FFR) schemes have been proposed in literature, with the mos... more Different fractional frequency reuse (FFR) schemes have been proposed in literature, with the most common being the two-layer scheme. In this scheme, the cell is divided into an inner region and an outer region. Different frequency sub-bands are used in each region, with the inner region typically having a reuse-1 scheme and the outer region a reuse-3 scheme. This has been shown to be effective in reducing inter-cell interference and subsequently improving reception for the cell edge users. This paper investigates the effect of using different schedulers in the inner and outer regions of a two-layer FFR scheme. The schedulers chosen for evaluation are the proportional fair scheduler and the round robin scheduler. Different scheduler combinations are investigated for various values of β_FR to evaluate performance trends. Metrics considered for evaluation are the mean, peak and edge throughput, as well as fairness. Simulation results clearly show that the proportional fair scheduler o...

Research paper thumbnail of Selection of Optimal SINR Threshold in Fractional Frequency Reuse by Comparing Otsu's and Entropy Method

SSRN Electronic Journal, 2022

Research paper thumbnail of Optimization of Base Station Location in 3G Networks using Mads and Fuzzy C-means

Network and Complex Systems, 2013

Distribution of Base Transceiver Stations (BTS) with an aim of maintaining high Quality of Servic... more Distribution of Base Transceiver Stations (BTS) with an aim of maintaining high Quality of Service and coverage is important to mobile operators. Rapid expansion of telecommunication industry results in stiff competition among service providers which in turn leads to greater focus on quality of services delivered. Increase in number of mobile phone usage has also led to unprecedented network expansion. Coupled to these challenges is rapid change in telecommunication technology from 2G to 4G in a short space of time. A combination of MADS and FUZZY C- MEANS is used to aid in planning Base Station Transceivers (BTS) location efficiently in order to curb capital and maintenance costs. Keywords: BTS placement, MADS, Fuzzy C-Means

Research paper thumbnail of Optimization of Base Station Location in 3G Networks using Fuzzy Clustering and Mesh Adaptive Direct Search

This paper addresses the problem of optimal distribution of Base Transceiver Stations (BTS) while... more This paper addresses the problem of optimal distribution of Base Transceiver Stations (BTS) while maintaining acceptable Quality of Service. Expansion of telecommunication industry results in stiff competition among service providers which leads to focus on quality of services delivered. Increase in number of mobile phone usage has also led to unprecedented increase in network traffic. This paper also shows how optimal BTS locations shift when Mobile Stations (MS) increase.

Research paper thumbnail of Fractional Frequency Reuse Optimal SINR Threshold Selection Using NIR and ISODATA

Telecom

A vital part of cellular network evolution has been long-term evolution networks. In these networ... more A vital part of cellular network evolution has been long-term evolution networks. In these networks, it is important to mitigate inter-cell interference. Fractional frequency re-use has been proposed to address this. The method involves the division of cells into two regions based on a signal-to-interference-plus-noise-ratio threshold value. The inner region adopts a frequency re-use of one (1), while the outer region uses a higher frequency re-use factor. Setting the threshold value is a critical problem addressed in this paper. The proposed approach adapts techniques used in image processing called global-thresholding techniques. The approaches considered are iterative self-organizing data analysis and native integral ratio. Mobile stations in a cell continuously report their signal-to-interference-plus-noise-ratio values to the base station. These reported values are used to determine a threshold which dictates which subscribers fall in the inner and outer regions. The threshold ...

Research paper thumbnail of Evaluation Of Different Transmission Modes In Coordinated Homogeneous And Heterogeneous Networks

LTE supports different transmission modes such as: Single Input Single Output (SISO), Transmissio... more LTE supports different transmission modes such as: Single Input Single Output (SISO), Transmission diversity (TxD) and Multiple Input Multiple Output (MIMO). TxD aims at improving the signal strength at the receiver by using two or more transmit antennas while MIMO techniques are used to increase the throughput according to the number of antennas used. Coordinated Multipoint (CoMP) techniques reduce interference and improve signal strength. Homogeneous networks consist entirely of macrocells while heterogeneous networks (HetNets) have both macrocells and femtocells. HetNets are used to meet increased mobile traffic demands by providing low power nodes closer to the user equipment. This paper reviews popular transmission modes and investigates their performance in both homogeneous and heterogenous CoMP networks. Simulation of the different transmission modes is carried out and results show that CLSM is the best transmission mode to use in in homogeneous networks, and that CLSM and OL...

Research paper thumbnail of Optimal SINR Threshold Selection In Fractional Frequency Reuse Using Otsu ’ s Method

Fractional Frequency Re-use (FFR) is a popular technique for controlling inter-cell interference ... more Fractional Frequency Re-use (FFR) is a popular technique for controlling inter-cell interference in OFDMA cellular networks. FFR involves dividing each cell into inner and outer layers, with different frequency re-use ratios for each layer. Important design parameters in FFR are the signal-tointerference-plus-noise ratio (SINR) threshold, , and the frequency allocation ratio, . In conventional FFR schemes, and are fixed and do not vary with cell conditions. A dynamic FFR scheme is developed where the optimal SINR threshold is determined using Otsu’s method, a digital image processing technique. The optimal SINR threshold is calculated based on periodic SINR values in the cells, and then set proportionately to the number of users in each layer. The designed system is evaluated through system-level simulations is found to outperform conventional FFR in terms of both throughput and fairness. Index items: LTE, FFR, Otsu’s Method, Spectral efficiency, Fairness. ——————————  —————————— Op...

Research paper thumbnail of Performance Evaluation Of Proportional Fair And Round Robin Schedulers In Two-Layer Ffr

Different fractional frequency reuse (FFR) schemes have been proposed in literature, with the mos... more Different fractional frequency reuse (FFR) schemes have been proposed in literature, with the most common being the two-layer scheme. In this scheme, the cell is divided into an inner region and an outer region. Different frequency sub-bands are used in each region, with the inner region typically having a reuse-1 scheme and the outer region a reuse-3 scheme. This has been shown to be effective in reducing inter-cell interference and subsequently improving reception for the cell edge users. This paper investigates the effect of using different schedulers in the inner and outer regions of a two-layer FFR scheme. The schedulers chosen for evaluation are the proportional fair scheduler and the round robin scheduler. Different scheduler combinations are investigated for various values of β_FR to evaluate performance trends. Metrics considered for evaluation are the mean, peak and edge throughput, as well as fairness. Simulation results clearly show that the proportional fair scheduler o...