Browsing by Author "Mtonyole, Nixon"

Now showing 1 - 7 of 7
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    Comparison of convergence and BER performance on LMS, RLS and NLMS in BPLC systems
    (International Journal of Science and Research, 2012) Mjahid, Mohammed; Mtonyole, Nixon
    Adaptive equalization techniques compensate for timechannels dispersion introduced by band limited or frequency selective communication channel and combat the resulting inter-symbol interference (ISI) effect. When signals are transmitted on broadband power-line (BPL) channel, they undergo severe distortions. Typically, adaptive equalizers used in digital communication systems like BPL systems require an initial training period, during which a known data sequence is transmitted. A replica of this sequence is made available at the receiver in proper synchronization with the transmitter, making it possible for adjustments to be made to the equalizer coefficients in accordance with the adaptive filtering algorithm. However, in this paper, three algorithms for adapting transversal filter coefficient were studied, to compare their adaptation rate and BER performance on BPL channel. It has been shown that normalized least mean square (NLMS) algorithm performs better with a rate of convergence of about 150 iterations with an approximate MSE value of 25dB and with an Eb/No of 13dB NLMS algorithm achieve a BER of 10-5 compared to least mean square (LMS) and recursive least square (RLS) having a BER of 5×10-5 and 10-2 respectively.
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    Design of multicarrier broadband power line communication system for Tanzania homes
    (Foundation of Computer Science, 2014) Victor, Crallet; Mtonyole, Nixon
    Broadband Power Line Communication (BPLC) is a method of providing broadband internet access to consumers using High Frequency (HF) radio signals coupled into the mains power wiring. In the BPLC system, data signals are modulated at HF and injected into the power lines using broadband modulation techniques. Design of a BPLC system requires a complete understanding of the Power line network (PLN) topologies involved. PLN can be classified as Indoor or In-home, Low voltage, Medium voltage and High voltage respectively. In this study four maps representing typical Tanzania houses were selected randomly, and then four indoor power-line networks were derived from their circuit diagrams. The Impulse response was estimated at the switch sockets using the recent power-line channel model by Anatory et al. The delay spread estimated from the impulse response was used to design the OFDM system and the OFDM system performance was evaluated.
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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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    Performance analysis of multiple access techniques for broadband power line communication system
    (Tylor & Francis, 2014) Victor, Crallet; Shao, Bertha; Mtonyole, Nixon
    Broadband over power lines is the way of providing internet services to customers using high frequency signals integrated in the power wiring. For uplink internet services data signals are modulated and coupled into the overhead power lines. For the downlink data signals are decoupled at the consumer’s premises. BPL can be a solution for people living rural area where there is electricity, since the cost of laying network cables and building the necessary infrastructure to every house is too high. BPL can serve to cut down the costs by eliminating the need for laying new infrastructure. A successful deployment of BPL requires a MAC layer that can cope with powerline channel impairments. The purpose of MAC layer is to provide a multiple access scheme, resource sharing and traffic control functions. Multiple access schemes divide up to the total signaling resource into channels and then assign these channels to different users. To achieve that the transmission medium is divided along the time, frequency and/or code axes. There are various multiple access schemes, but in this paper FDMA and TDMA are the two multiple access schemes which are taken into consideration. Their performances under different channel conditions have been found. The channel conditions considered are low, medium and high disturbances. It was found that TDMA performsbetter than FDMA under all these channel conditions
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    Software based traffic separation at the access layer
    (Scholastic Scientific Publishing, 2014) Andegelile, Yona; Mtonyole, Nixon
    Access Network is the subscriber part of the telecommunications network or the network connecting the subscribers to the Internet Service Providers (ISP) [1]. In many countries including Tanzania access network is still predominantly made up of the copper cable based or other point to point wireless connections. This has kept the network in large proportions passive, inflexible and relatively unreliable [2]. This traditional network has long been tailored to the services generally provided i.e. voice, leased lines, Internet, corporate data and video conference, sometimes each provided by separate equipment and networks. This paper presents the study on approaches used by ISP in Tanzania to separate traffic in the access network. The paper also presents the effective way of traffic separation, whereby multiple hardware used to separate traffic currently has been replaced with single hardware. The traffic separation technique is based on creating logical links (software based) for each traffic type inside single physical link, providing a differentiated QoS support for each type of traffic according to its individual QoS requirements
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    The use of mobile phones in university exams cheating: proposed solution
    (Seventh Sense Research Group, 2014) Nyamawe, Ally S.; Mtonyole, Nixon
    Currently, instant communication is very possible all over the world due to a rapid growth in mobile phones technology. Each day, a number of mobile phones subscribers and cellular network coverage is escalating tremendously. Today’s mobile phones are released with ability nearly to that of a desktop computer. The ubiquity nature of mobile phones and extended network coverage allows for constant connectivity, easy flow of information and accessibility. Students use mobile phones to store lecture materials, tutorials, communicate with colleagues and surf the internet for different purposes. These advantages would have adverse effects if mobile phones will be brought in restricted premises such as exam venues. Disobedient candidates use mobile phones to cheat in exams. In this paper, we propose a system prototype that will be used to detect mobile phones in the exam venues.
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    Voice quality analysis for software based traffic separation at the access layer of hierarchical design model
    (Taylor and Francis Ltd, 2014) Mtonyole, Nixon; Andegelile, Yona
    In many countries including Tanzania access network is still predominantly made up of the copper cable or point to point wireless connections. This has kept the network in large proportions passive, inflexible and relatively unreliable. Software based traffic separation at the access layer is a technique that is used to reduce the number of physical links to customer premises. This paper performs quality analysis for voice transmitted through such links (i.e. logical links) and it is observed that there is no major difference as to when dedicated physical links are used.