发布求助
文献互助 智能选刊 最新文献

2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)最新文献

筛选
英文 中文
The need for standardization and regulation on electromagnetic compatibility in Africa 非洲对电磁兼容性进行标准化和管理的必要性
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406729
A. Ogunsola
{"title":"The need for standardization and regulation on electromagnetic compatibility in Africa","authors":"A. Ogunsola","doi":"10.1109/AFRICON.2004.1406729","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406729","url":null,"abstract":"Africa is an import oriented continent with a significant percentage of all electronics and electrical equipment imported, as new or second hand, from other developed nations. The explosion of the telecommunications industry in Africa is an indication of the potential market in this great continent, with an estimated market of 15 million subscribers to GSM technology in Nigeria alone. As Africa increases its participation as users (and most importantly as stakeholders) of technology, the importance of electromagnetic compatibility and bio-electromagnetics increasingly becomes an issue. The paper describes EMC, its potential impact and the need for regulation in an increasing industrialized Africa","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129086836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Scheduler performance evaluation and the effect of aggregation on QoS in a DiffServ enabled network 在启用DiffServ的网络中，调度器性能评估和聚合对QoS的影响
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406685
J. J. Smit, H. Ferreira
{"title":"Scheduler performance evaluation and the effect of aggregation on QoS in a DiffServ enabled network","authors":"J. J. Smit, H. Ferreira","doi":"10.1109/AFRICON.2004.1406685","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406685","url":null,"abstract":"Various network traffic models exist that describe network traffic behaviour, but no model describes differential traffic treatment to such an extent to be able to relate the impact different rates has on the various traffic classes. With computer network simulation, we evaluate four different standardized PHBs, namely EF, AF1, AF2 and BE. The PQ, SFQ, SCFQ, WFQ, WF2Q+ and LLQ scheduling mechanisms are analysed to find their performance in relation to EF traffic as well as the effects of different traffic aggregation schemes on them. The QoS factors we focus on are: one-way delay, queue lengths and inter-packet delay variation. Network topologies are large and are defined by various parameters, thus our simulations are performed using acceptable bounded properties","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124966549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
A radio frequency MOSFET driver 一个射频MOSFET驱动器
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406737
A. Swart, H.C.V. Pienaar, M. Case
{"title":"A radio frequency MOSFET driver","authors":"A. Swart, H.C.V. Pienaar, M. Case","doi":"10.1109/AFRICON.2004.1406737","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406737","url":null,"abstract":"High power MOSFETs have become synonymous with power electronics applications. The ability of high power MOSFETs to act as a switch makes it the ideal switching device, where maximum voltage and zero current must occur when the device is open. When closed, the MOSFET must allow maximum current to flow with zero voltage across it. This technique of switching between maximum and zero voltage across the high power MOSFET is readily achieved at frequencies below 1 MHz. Raising the frequency to within the radio frequency range has often proved a problem since high power MOSFETs tend to have a frequency cut-off point. This paper attempts to address the switching habits and limits of high power MOSFETs within the radio frequency range by means of computer simulation and experimental verification","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129639799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Realizing multimedia distance education based on DVB and GSM data services 实现基于DVB和GSM数据业务的多媒体远程教育
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406891
J. Steyn, H. Ferreira, C. van der Westhuizen, W. A. Clarke
{"title":"Realizing multimedia distance education based on DVB and GSM data services","authors":"J. Steyn, H. Ferreira, C. van der Westhuizen, W. A. Clarke","doi":"10.1109/AFRICON.2004.1406891","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406891","url":null,"abstract":"Multimedia services are exploited in a variety of different applications such as telemedicine, distance education, video conferencing, etc. In this study innovative ways of realizing multimedia distance education through satellite and cellular communications are investigated. Focus is on African scenarios that require affordable, available and low technical-literacy-requirement solutions. A satellite link from teacher to students is used, completed by a GSM/cellular return path (from student back to the teacher). These two network infrastructures are well in place and accessible through out higher populated areas in Sub-Saharan Africa. This research aims to facilitate a multimedia distance education service on the proposed set up and then to assess system performance (bit rate consumption-cost, packet loss, jitter/unequal packet arrival intervals, round trip delays, etc.). Data/IP services available on GSM networks (SMS and GPRS) and satellite networks (DVB data broadcasting) are implemented. The flexibility of this system promises to deliver rich multimedia at scalable content/cost.","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130317827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Convergence analysis of iterative interference cancellation receivers for turbo-coded DS-CDMA systems 涡轮编码DS-CDMA系统中迭代干扰抵消接收机的收敛性分析
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406658
E. Bejide, F. Takawira
{"title":"Convergence analysis of iterative interference cancellation receivers for turbo-coded DS-CDMA systems","authors":"E. Bejide, F. Takawira","doi":"10.1109/AFRICON.2004.1406658","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406658","url":null,"abstract":"We investigate the behaviour of iterative interference cancellation receivers in turbo-coded DS-CDMA systems. We propose a methodology for the convergence analysis of the receivers. Our method is based on the Gaussian approximation technique. Analytical expressions for the SNR transfer function of the interference cancellation stage of the receiver are presented. This is in contrast to the semi-analytical approach that has been used in the literature to determine the variance transfer function of the interference cancellation stage. Results show that the proposed methodology is accurate for the convergence analysis of the iterative interference cancellation receiver","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130557626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Pairwise error probability on the Gilbert-Elliott channel with application to turbo codes 吉尔伯特-艾略特信道的成对误差概率及其在turbo码中的应用
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406674
T. Ngatched, F. Takawira
{"title":"Pairwise error probability on the Gilbert-Elliott channel with application to turbo codes","authors":"T. Ngatched, F. Takawira","doi":"10.1109/AFRICON.2004.1406674","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406674","url":null,"abstract":"The Gilbert-Elliott (GE) channel is one of the simplest and practical models for a channel with memory. In this paper, the performance of a binary linear code in a slowly varying Rayleigh fading channel modeled by the GE channel model is considered. An analytical expression for the pairwise error probability of maximum likelihood decoding of a binary linear code on the GE channel model is derived. This expression is obtained as a function of the channel parameters and can be used to obtain the union bound on the bit error probability of any binary linear code on the GE channel if the weight distribution or average weight distribution of the codewords is known. Comparisons between the results obtained by this analytical expression and results obtained through computer simulations in the case of turbo codes show that the analytical results are accurate in establishing the decoder performance in the range where obtaining sufficient data from simulation is impractical","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126700168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Wavelength tunable add/drop multiplexer for dense wavelength-division multiplexing using short- and long-period fiber gratings 波长可调的加/降复用器，用于使用短周期和长周期光纤光栅的密集波分复用
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406835
R. Kritzinger, P. Swart
{"title":"Wavelength tunable add/drop multiplexer for dense wavelength-division multiplexing using short- and long-period fiber gratings","authors":"R. Kritzinger, P. Swart","doi":"10.1109/AFRICON.2004.1406835","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406835","url":null,"abstract":"This work is primarily concerned with the utilization of fiber Bragg gratings (FBGs) and chirped long-period gratings (CLPGs) to realize a novel wavelength-tunable optical add/drop multiplexer (OADM) device. We considered the theory of fiber Bragg gratings and long-period gratings to explain the operation of the new device. The method of strain used for tuning of the fiber Bragg grating, channel isolation, and crosstalk between channels are also discussed.","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124221148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A proposal for secure software download in SDR 一种基于SDR的安全软件下载方案
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406637
D. Dawoud
{"title":"A proposal for secure software download in SDR","authors":"D. Dawoud","doi":"10.1109/AFRICON.2004.1406637","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406637","url":null,"abstract":"To promote the commercial implementation of software defined radio (SDR) terminals, a secure method of download is vital. The flexibility of the system to change from one environment to the other and the possibility of changing any cryptographic component at any time is also an important issue. In this paper we are discussing three main design metrics of SDR. A proposed protocol for changing any cryptographic component is proposed","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"06 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123384399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
A business case for the sharing of processing power between 2.5G mobile phones 2.5G手机处理能力共享的商业案例
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406690
A. Gazendam, Y. Kaka
{"title":"A business case for the sharing of processing power between 2.5G mobile phones","authors":"A. Gazendam, Y. Kaka","doi":"10.1109/AFRICON.2004.1406690","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406690","url":null,"abstract":"Current 2.5G mobile phones, and the coming wave of mobile phones conforming to the specifications of 3G and beyond, have great potential to be utilized as nodes in what is referred to as \"wireless grids\". Many modern mobile phones have processing power comparable to that of personal computers of a few years ago. This attribute, in combination with the vast numbers of mobile phones being sold every year and their various connectivity options, make mobile phones interesting candidates for distributed processing nodes. The ad-hoc networking benefits of Bluetooth and \"always-online\" characteristic of GPRS are networking benefits that could well compensate for relatively low user-level data rates of 2.5G networks when compared to that of conventional computer networks. The programming options provided by Java, Microsoft and Symbian environments on modern mobile phones enable development of the client-side software necessary for the wireless grid","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123539547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
xDSL as a broadband solution for the developing countries xDSL作为发展中国家宽带解决方案
2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590) Pub Date : 2004-09-15 DOI: 10.1109/AFRICON.2004.1406651
Z. Mbebe, R. Sewsunker
{"title":"xDSL as a broadband solution for the developing countries","authors":"Z. Mbebe, R. Sewsunker","doi":"10.1109/AFRICON.2004.1406651","DOIUrl":"https://doi.org/10.1109/AFRICON.2004.1406651","url":null,"abstract":"Developing countries present a graphic picture of the digital divide. This is the result of locating previously disadvantaged people in underdeveloped areas. These areas are characterized by a high rate of unemployment and a poor level of education. This results in a scenario where most of the residents are unable to utilize IT resources. Some people in these areas are not informed about the availability and importance of these technologies in the market. Those who are academically fit for accessing these technologies often cannot afford them. High deployment costs associated with broadband services makes it even more challenging to deploy such services in this environment. Approximately 80% of the population in Africa is rural, which alone creates a demand for the coverage of rural regions. In this research, it is shown that broadband services can be delivered to rural people by applying xDSL technologies, using the existing telecommunications infrastructure. With this technology a number of different high bandwidth services can be delivered to homes, schools, hospitals, telecentres and small businesses","PeriodicalId":224116,"journal":{"name":"2004 IEEE Africon. 7th Africon Conference in Africa (IEEE Cat. No.04CH37590)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116197025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：604180095
Book学术官方微信
小红书