Browsing by Author "Anatory, Justinian"

Now showing 1 - 6 of 6
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    Cost effective coverage and capacity optimization in wireless cellular networks
    (Hindawi Publishing Corporation, 2013) Anatory, Justinian; Kalolo, Sadath; Sam, Anael; Machuve, Dina
    Coverage and capacity optimization of the fast growing wireless cellular networks is a tedious task and requires huge investment in network resources. Most techniques for coverage and capacity optimization result into increase in network complexity, radio frequency interferences, capital expenditure (CAPEX) and operational expenses (OPEX). The extensive growth of the wireless cellular industry, high penetration of wireless cellular networks and the need for low cost services to end users coupled with the proliferation of use of multimedia applications demands for other measures to optimize both coverage and capacity in wireless cellular networks. This work presents a cost effective coverage and capacity optimization method for wireless cellular networks that takes into account both CAPEX and OPEX considerations while ensuring guaranteed Quality of Services (QoS) to end users. The method allows incoming traffic overflows into neighbor network to utilize available coverage and capacity in those networks when there are inadequate resources in the home network. Performance evaluation of the formulated method using MATLAB simulations reveals significant improvement of Quality of Services offered to subscribers.
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    Investigating the factors affecting broadband adoption in Tanzania: a case of Dares Salaam, Tanzania
    (Foundation of Computer Science, 2014) Nyondo, Samson; Anatory, Justinian; Mtonyole, Nixon
    Broadband access has become an important resource for individuals and communities. A high-speed connection to the internet provides opportunities for many economic, social and cultural benefits. Recent researches in developing countries points to the appalling broadband penetration rates in these countries. An understanding of the factors affecting broadband adoption in these countries is a key to any strategy to improve broadband penetration figures. This paper examined several attitudinal, normative and control factors as identified from literature to provide insights of broadband adopters and non-adopters in Tanzania. The findings suggested that the utilitarian outcomes and relative advantage were the major factors influencing consumers’ decision to adopt broadband in Tanzania. The findings from regression analysis also showed that the relative advantage, utilitarian outcomes and self-efficacy factors were more significant in explaining consumers’ behavioral intention to adopt broadband. On the other hand, the “expenses of broadband services” and “lack of appropriate equipment to access broadband”, had the highest importance rating among the barriers to adopt broadband in Tanzania.
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    Investigation of radio propagation characteristics in UHF band over straight and circular paths in central Tanzania
    (IEEE, 2021) Matogoro, Jabhera; Mfupe, Luzango; Mvungi, Nerei; Anatory, Justinian
    A study was conducted to investigate radio propagation characteristics in ultra-high frequency (UHF) bands over straight and circular paths in central Tanzania. The received signal power values (in dBm) were collected using a spectrum analyzer in straight and circular paths. The collected values were further converted to path loss values and validated against those computed from theoretical formulas of ITU-R P.452-16, ITU-R P.1812-4, Hata and Longley-Rice models. The study used the experimental spectrum measurements approach and Pearson’s correlation coefficient (PCC) to determine the best-fit propagation model for the UHF spectrum band allocated for digital terrestrial television (DTT) in central Tanzania. The DTT spectrum band ranges from 470 – 694 MHz in Tanzania after successfully migrating from analogue to digital broadcasting. The study found a significant difference between measured path loss values and those computed from theoretical formulas. The Hata and Longley-Rice models had a better convergence with reality for most of the fixed locations. The accuracy of the empirical propagation model plays a critical role in the optimal planning of the television white space (TVWS) network and contributes to efficient spectrum utilization.
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    Performance improvement of MAC protocols for broadband power-line access networks of developing countries: A case of Tanzania
    (2013) Abdalla, Abdi T.; Anatory, Justinian
    This paper investigates the possibility of improving throughputs of some Media Access Controls protocols such as ALOHA, slotted ALOHA and Carrier Sense Multiple Access with Collision Avoidance with the aim of increasing the performance of Powerline access networks. In this investigation, the real Powerline network topology in Tanzania located in Dar es Salaam City, Kariakoo area was used as a case study. During this investigation, Wireshark Network Protocol Analyzer was used to analyze data traffic of similar existing network for projection purpose and then the data were simulated using MATLAB. This paper proposed and analyzed three improvement techniques based on collision domain, packet length and combination of the two. From the results, it was found that the throughput of Carrier Sense Multiple Access with Collision Avoidance protocol improved noticeably while ALOHA and slotted ALOHA showed insignificant changes especially when the hybrid techniques were employed. Keywords—Access Network, ALOHA, Broadband Powerline Communication, Slotted ALOHA, CSMA/CA and MAC Protocols.
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    A price based spectrum sharing scheme in wireless cellular networks
    (The International Institute for Science, Technology and Education (IISTE), 2013) Kalolo, Sadath; Sam, Anael; Machuve, Dina; Anatory, Justinian
    Radio frequency spectrum scarcity has become a high priority research area over the past few years. The huge increase of network subscribers with multimedia applications coupled with underutilization of radio frequency spectrum motivates the search for other measures to address the scarcity of radio frequency spectrum. This work investigates on a price based spectrum sharing scheme for connection-oriented traffic in wireless cellular networks as a solution to address the scarcity of radio frequency spectrum. Dynamic pricing approach is applied with traffic overflows into neighbor networks. Performance evaluations of the scheme at steady state using MATLAB simulations reveal significant gains to the quality of service. Application of the scheme to highly loaded network traffic improves both network revenue and traffic channel utilizations.
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    Safety zone determination for wireless cellular tower - a case study from tanzania
    (IJRET, 2013) Nyakyi, Christina P.; Mrutu, Salehe I.; Sam, Anael; Anatory, Justinian
    Safety zone determination for wireless cellular towers has attracted attention from many researchers in the last decade. This is caused by the rapid growth of the wireless cellular industry which has led to the installation of towers even in the residential areas. There are many reports and ongoing researches regarding the biological and thermal effects of wireless cellular electromagnetic fields exposures to people. Cancer, hyperthermia, neural and behaviour effects of people exposed to these electromagnetic fields have been reported. This motivates the research to determine safety zones from wireless cellular towers to assure safety to those living in the vicinity of these towers. A model for safety zone determination is developed. The model takes the received power at the object, power transmitted by the transmitter and gain of the transmitter as inputs to determine the safe distance from the radiation of a wireless cellular transmitter. The power density received by the object and its geographical location from the radiation source are measured using the selective radiation meter. Transmitted power and the gain of the transmitter together with the height of the tower were obtained from the respective wireless cellular network operator. Based on the geographical location of the object, the distance from the radiation source was calculated using the haversine formula. These inputs are then used to determine the safety zone based on the standards and guidelines developed by WHO and ICNIRP.