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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Cellular radio networks systems engineering.

January 1995 (has links)
by Kwan Lawrence Yeung. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 115-[118]). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Cellular Concept --- p.1 / Chapter 1.2 --- Fixed Channel Assignment --- p.2 / Chapter 1.3 --- Dynamic Channel Assignment --- p.2 / Chapter 1.4 --- Performance Evaluation of DC A --- p.3 / Chapter 1.5 --- Han doff Analysis --- p.3 / Chapter 1.6 --- Mobile Location Tracking Strategies --- p.3 / Chapter 1.7 --- QOS Measure --- p.4 / Chapter 1.8 --- Organization of Thesis --- p.4 / Chapter 2 --- Optimization of Channel Assignment I --- p.6 / Chapter 2.1 --- Introduction --- p.6 / Chapter 2.2 --- Generating Compact Patterns --- p.7 / Chapter 2.2.1 --- Regular size cells --- p.7 / Chapter 2.2.2 --- Irregular size cells --- p.7 / Chapter 2.3 --- Nominal Channel Allocation Methods --- p.10 / Chapter 2.3.1 --- Compact pattern allocation --- p.10 / Chapter 2.3.2 --- Greedy allocation --- p.11 / Chapter 2.3.3 --- Hybrid allocation --- p.11 / Chapter 2.3.4 --- The K-Optimal variations --- p.11 / Chapter 2.3.5 --- Backtracking strategies --- p.12 / Chapter 2.4 --- Performance Comparison --- p.12 / Chapter 2.5 --- Conclusions --- p.16 / Chapter 3 --- Optimization of Channel Assignment II --- p.18 / Chapter 3.1 --- Introduction --- p.18 / Chapter 3.2 --- Basic Heuristics --- p.20 / Chapter 3.2.1 --- Two methods for cell ordering --- p.20 / Chapter 3.2.2 --- Two channel assignment strategies --- p.20 / Chapter 3.3 --- Channel Assignments with Cell Re-ordering --- p.21 / Chapter 3.3.1 --- Four channel assignment algorithms --- p.21 / Chapter 3.3.2 --- Complexity --- p.22 / Chapter 3.3.3 --- An example --- p.22 / Chapter 3.4 --- Channel Assignment at Hotspots --- p.23 / Chapter 3.4.1 --- Strategy F vs strategy R --- p.23 / Chapter 3.4.2 --- Strategy FR --- p.24 / Chapter 3.5 --- Numerical Examples --- p.25 / Chapter 3.5.1 --- "Performance of algorithms F/CR,F/DR,R/CR and R/DR" --- p.26 / Chapter 3.5.2 --- Effect of X & Y on performance of algorithms FR/CR & FR/DR --- p.26 / Chapter 3.5.3 --- Performance of algorithms FR/CR & FR/DR --- p.27 / Chapter 3.6 --- Conclusions --- p.27 / Chapter 4 --- Compact Pattern Based DCA --- p.29 / Chapter 4.1 --- Introduction --- p.29 / Chapter 4.2 --- Compact Pattern Channel Assignment --- p.30 / Chapter 4.2.1 --- Data structures --- p.30 / Chapter 4.2.2 --- Two functions --- p.31 / Chapter 4.2.3 --- Two phases --- p.32 / Chapter 4.3 --- Performance Evaluation --- p.33 / Chapter 4.4 --- Conclusions --- p.36 / Chapter 5 --- Cell Group Decoupling Analysis --- p.37 / Chapter 5.1 --- Introduction --- p.37 / Chapter 5.2 --- One-Dimensional Cell Layout --- p.38 / Chapter 5.2.1 --- Problem formulation --- p.38 / Chapter 5.2.2 --- Calculation of blocking probability --- p.39 / Chapter 5.3 --- Two-Dimensional Cell Layout --- p.41 / Chapter 5.3.1 --- Problem formulation --- p.41 / Chapter 5.3.2 --- Calculation of blocking probability --- p.42 / Chapter 5.4 --- Illustrative Examples --- p.42 / Chapter 5.4.1 --- One-dimensional case --- p.42 / Chapter 5.4.2 --- Two-dimensional case --- p.45 / Chapter 5.5 --- Conclusions --- p.45 / Chapter 6 --- Phantom Cell Analysis --- p.49 / Chapter 6.1 --- Introduction --- p.49 / Chapter 6.2 --- Problem Formulation --- p.49 / Chapter 6.3 --- Arrival Rates in Phantom Cells --- p.50 / Chapter 6.4 --- Blocking Probability and Channel Occupancy Distribution --- p.51 / Chapter 6.4.1 --- Derivation of α --- p.51 / Chapter 6.4.2 --- Derivation of Bside --- p.52 / Chapter 6.4.3 --- Derivation of Bopp --- p.53 / Chapter 6.4.4 --- Channel occupancy distribution --- p.54 / Chapter 6.5 --- Numerical Results --- p.55 / Chapter 6.6 --- Conclusions --- p.55 / Chapter 7 --- Performance Analysis of BDCL Strategy --- p.58 / Chapter 7.1 --- Introduction --- p.58 / Chapter 7.2 --- Borrowing with Directional Carrier Locking --- p.58 / Chapter 7.3 --- Cell Group Decoupling Analysis --- p.59 / Chapter 7.3.1 --- Linear cellular systems --- p.59 / Chapter 7.3.2 --- Planar cellular systems --- p.61 / Chapter 7.4 --- Phantom Cell Analysis --- p.61 / Chapter 7.4.1 --- Call arrival rates in phantom cells --- p.62 / Chapter 7.4.2 --- Analytical model --- p.62 / Chapter 7.5 --- Numerical Examples --- p.63 / Chapter 7.5.1 --- Linear cellular system with CGD analysis --- p.63 / Chapter 7.5.2 --- Planar cellular system with CGD analysis --- p.65 / Chapter 7.5.3 --- Planar cellular system with phantom cell analysis --- p.65 / Chapter 7.6 --- Conclusions --- p.68 / Chapter 8 --- Performance Analysis of Directed Retry --- p.69 / Chapter 8.1 --- Introduction --- p.69 / Chapter 8.2 --- Directed Retry Strategy --- p.69 / Chapter 8.3 --- Blocking Performance of Directed Retry --- p.70 / Chapter 8.3.1 --- Analytical model --- p.70 / Chapter 8.3.2 --- Numerical examples --- p.71 / Chapter 8.4 --- HandofF Analysis for Directed Retry --- p.73 / Chapter 8.4.1 --- Analytical model --- p.73 / Chapter 8.4.2 --- Numerical examples --- p.75 / Chapter 8.5 --- Conclusions --- p.77 / Chapter 9 --- Handoff Analysis in a Linear System --- p.79 / Chapter 9.1 --- Introduction --- p.79 / Chapter 9.2 --- Traffic Model --- p.80 / Chapter 9.2.1 --- Call arrival rates --- p.80 / Chapter 9.2.2 --- Channel holding time distribution --- p.81 / Chapter 9.3 --- Analytical Model --- p.81 / Chapter 9.3.1 --- Handoff probability --- p.81 / Chapter 9.3.2 --- Handoff call arrival rate --- p.81 / Chapter 9.3.3 --- Derivation of blocking probability --- p.81 / Chapter 9.3.4 --- Handoff failure probability --- p.82 / Chapter 9.3.5 --- Finding the optimal number of guard channels --- p.83 / Chapter 9.4 --- Numerical Results --- p.83 / Chapter 9.4.1 --- System parameters --- p.83 / Chapter 9.4.2 --- Justifying the analysis --- p.84 / Chapter 9.4.3 --- The effect of the number of guard channels --- p.84 / Chapter 9.5 --- Conclusions --- p.85 / Chapter 10 --- Mobile Location Tracking Strategy --- p.88 / Chapter 10.1 --- Introduction --- p.88 / Chapter 10.2 --- Review of Location Tracking Strategies --- p.89 / Chapter 10.2.1 --- Fixed location area strategy --- p.89 / Chapter 10.2.2 --- Fixed reporting center strategy --- p.89 / Chapter 10.2.3 --- Intelligent paging strategy --- p.89 / Chapter 10.2.4 --- Time-based location area strategy --- p.89 / Chapter 10.2.5 --- Movement-based location area strategy --- p.90 / Chapter 10.2.6 --- Distance-based location area strategy --- p.90 / Chapter 10.3 --- Optimization of Location Area Size --- p.90 / Chapter 10.3.1 --- Location updating rates ´ؤ linear systems --- p.90 / Chapter 10.3.2 --- Location updating rates ´ؤ planar systems --- p.91 / Chapter 10.3.3 --- Optimal location area size ´ؤ linear systems --- p.92 / Chapter 10.3.4 --- Optimal location area size ´ؤ planar systems --- p.92 / Chapter 10.4 --- Comparison of FLA & DBLA Strategies --- p.93 / Chapter 10.5 --- Adaptive Location Tracking Strategy --- p.94 / Chapter 10.5.1 --- Mobility tracking --- p.94 / Chapter 10.5.2 --- Protocols for ALT strategy --- p.94 / Chapter 10.6 --- Numerical Examples --- p.95 / Chapter 10.7 --- Conclusions --- p.97 / Chapter 11 --- A New Quality of Service Measure --- p.99 / Chapter 11.1 --- Introduction --- p.99 / Chapter 11.2 --- QOS Measures --- p.99 / Chapter 11.3 --- An Example --- p.101 / Chapter 11.4 --- Case Studies --- p.101 / Chapter 11.5 --- Conclusions --- p.106 / Chapter 12 --- Discussions & Conclusions --- p.107 / Chapter 12.1 --- Summary of Results --- p.107 / Chapter 12.2 --- Topics for Future Research --- p.108 / Chapter A --- Borrowing with Directional Channel Locking Strategy --- p.110 / Chapter B --- Derivation of p2 --- p.112 / Chapter C --- Publications Derived From This Thesis --- p.114 / Bibliography --- p.115
22

Distributed power control via stochastic approximation.

January 2003 (has links)
Weiyan Ge. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 64-68). / Abstracts in English and Chinese. / Abstract --- p.ii / Acknowledgement --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction of Power Control Problem --- p.2 / Chapter 1.1.1 --- Classification of Power Control Problem --- p.2 / Chapter 1.1.2 --- Previous Works --- p.7 / Chapter 1.2 --- Scope and Contribution of the Thesis --- p.11 / Chapter 1.3 --- Organization of the Thesis --- p.12 / Chapter 2 --- Background --- p.14 / Chapter 2.1 --- Stochastic Approximation --- p.14 / Chapter 2.2 --- Lognormal Distribution --- p.17 / Chapter 2.2.1 --- Definition and Properties --- p.17 / Chapter 2.2.2 --- Application on Radio Propagation --- p.18 / Chapter 3 --- System Model and Centralized Algorithm --- p.21 / Chapter 3.1 --- System Model --- p.21 / Chapter 3.2 --- Problem Statement and the Centralized Algorithm --- p.25 / Chapter 4 --- Proposed Stochastic Power Control Algorithm --- p.30 / Chapter 4.1 --- Proposed Power Control Algorithm --- p.30 / Chapter 4.2 --- Basic Properties of the Algorithm --- p.33 / Chapter 4.3 --- Convergence Property --- p.38 / Chapter 5 --- Numerical Results --- p.44 / Chapter 5.1 --- Simulation Model --- p.44 / Chapter 5.2 --- Numerical Results --- p.47 / Chapter 6 --- Conclusions And Future Works --- p.58 / Chapter 6.1 --- Conclusions --- p.58 / Chapter 6.2 --- Future Works --- p.60 / Chapter A --- Basic Properties of LOG-Distribution --- p.62 / Bibliography --- p.64
23

Selected Student Characteristics Related to Academic Cell Phone Use

Pauley, David 01 December 2015 (has links)
The researcher addressed the need for understanding student perceptions and habits of academic cell phone use within a high school environment in regards to student characteristics. Data were gathered and analyzed in order to answer research questions regarding student perceptions of: (a) the usefulness of cell phones as an academic tool, (b) the use of cell phones within school and outside of school for academic purposes, (c) the encouragement of cell phone use to complete assignments, (d) the potential for distractions within the classroom occurring from cell phone use, and (e) the functionality of cell phones for completion of school work. A quantitative research design was used in this study. Data were collected through the employment of a researcher-designed cross-sectional survey to gather data from one point in time from 175 respondents. Quantitative data were analyzed by frequency distributions and cross tabulations of responses to closed-end survey questions. It was found that students favored the use of cell phones for academic purposes. The implications of this study show the potential for expanded cell phone use as academic tools in high schools as a medium to promote mobile learning.
24

none

Liu, Hsuan-Chih 30 July 2003 (has links)
none
25

A Case Study About Cell Phone Use by People in Rural Kenya

Eriksson, Evanjeline January 2008 (has links)
<p>The arrival of the cell phone in rural areas has taken Kenya by storm. It has turned out to be such an amazing transition happening since most people in the start, did not reckon its capacity to gradually become a lifestyle choice. It has certainly changed the way people communicate and becoming a natural necessity for people of Kenya. This can be seen from the numbers of cell phone units sold in the past years. The cell phones in Kenya have gone from 1 million in 2002 to 6.5 million in 2006. Some of this boost has found their way into the rural areas of Kenya and that is what this thesis focuses on. Through a qualitative research approach presented as a case study provide both vigorous descriptions and exiting information. The case study is based mainly on material from telephone interviews that were carried out with a selected sample of the population living in the countryside to obtain their points of view. In addition some opinions received in email form from an organization based in the western part of Kenya is included. A related email questionnaire was administered to one of the companies that sell cell phones in Kenya. Reference has been made to previous research to present some insightful frame of reference on this subject. In conclusion the people in rural parts of Kenya use the short messaging service (SMS) as the most cost effective way of communication. Furthermore, the M-Pesa function on that enables users to make money transactions is also widely used since most people in these areas do not have a bank account. The cell phone has transformed the job market and had a tremendous impact on running a business and made it easier to be available when looking for jobs. It is clear that the cell phone has brought practical, social and economical change and contributing to cultural enhancement. There is however future needs as to solve the battery charging which is a main problem that rural inhabitant have to deal with. This thesis finally shows that the penetration of the cell phone in rural Kenya is of great success. The cell phone is a technique to bridge the gap between cities and rural areas in Kenya.</p>
26

Quad-band global system for mobile communications complementary metal-oxide-semiconductor transmitter /

Lee, See Taur. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (p. 183-191).
27

A study of fixed channel assignment algorithms for cellular mobile radio systems

Thavarajah, Arunasala Iyer. January 1999 (has links)
published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy
28

Young adults' relationship intentions towards their cell phone network providers / by Liezl-Marié Kruger

Kruger, Liezl-Marie January 2010 (has links)
Marketers use relationship marketing in order to establish mutually beneficial long-term relationships with their customers as a means to retain these customers in the competitive market environment. Relationship marketing should, however, not be used to target each and every customer as not all customers want to build long-term relationships with organisations. In order to identify the most profitable customers to target through relationship marketing, organisations should consider their customers' relationship intentions to form long-term relationships with them. The primary objective of this study was to determine young adults' (aged 18 to 25) relationship intentions towards the South African cell phone network providers they use, namely Vodacom, MTN or Cell C. This was done by considering the five constructs used to measure relationship intention, namely involvement, expectations, forgiveness, feedback and fear of relationship loss. A focus group was used to determine which features related to cell phone network providers young adults consider when selecting a cell phone network provider. This data was used to develop a self-administered questionnaire, which was distributed among respondents studying at the Potchefstroom Campus of the North-West University in the North-West Provirice. A convenience (non­ probability) sampling method was used and a total of 315 respondents participated in this study. The distribution between the cell phone network providers was Vodacom (115), MTN (101) and Cell C (99). Initial data analysis revealed that 73% of respondents had high relationship intentions, while the remainder (26%) had low relationship intentions of forming long-term relationships with their respective cell phone network providers. By means of a factor analysis it was determined that the five relationship intention factors, namely involvement, expectations, forgiveness, feedback and fear of relationship loss, were valid and reliable to measure the relationship intentions of respondents. The results further indicated that respondents with a t"iigh relationship intention are more involved with thei r cell phone network providers and feared losing thei r relationships with their cell phone network providers more than those respondents with a low relationship intention. Furthermore, respondents from the different cell phone network providers do not view the five factors comprising relationship intention differently, but they do differ with regards to other factors related to cell phone network providers. It was found that the majority of respondents regard Vodacom (not necessarily the respondent's cell phone network provider) as the cell phone network provider with the latest technology, as being the quickest, having the best coverage, best handsets, coolest image and best service. The majority of respondents regard Cell C as being the cheapest and MTN as being the most expensive. Results also indicate that respondents' parents play an important role with regard to the choice of their cell phone network providers as the majority of respondents' parents initially chose the cell phone network providers and pay their cellular expenses. It is recommended that cell phone network providers should target young adults' parents with a view to gain a foothold in the young adult market. Furthermore, it is recommended that cell phone network providers should determine how their customers perceive them as compared with competitors in order to better position themselves and to improve communication with young adults. Most importantly, it is recommended that cell phone network providers should identify those young adults with high relationship intentions (those young adults who are more involved with and fear losing their relationship with the cell phone network provider more) in order to retain them by attempting to build long-term relationships with these young adults through dedicated relationship marketing efforts. Recommendations for future research include examining relationship intention with regards to other age groups (such as scholars and adults), other service industries and other geographical areas. Furthermore, the influence which young adults exert on decisions concerning cell phone network providers and the influence of parents on young adults' product and service choices, can be explored in future research by means of the family decision roles. / Thesis (M.Com. (Marketing Management))--North-West University, Potchefstroom Campus, 2010.
29

Young adults' relationship intentions towards their cell phone network providers / by Liezl-Marié Kruger

Kruger, Liezl-Marie January 2010 (has links)
Marketers use relationship marketing in order to establish mutually beneficial long-term relationships with their customers as a means to retain these customers in the competitive market environment. Relationship marketing should, however, not be used to target each and every customer as not all customers want to build long-term relationships with organisations. In order to identify the most profitable customers to target through relationship marketing, organisations should consider their customers' relationship intentions to form long-term relationships with them. The primary objective of this study was to determine young adults' (aged 18 to 25) relationship intentions towards the South African cell phone network providers they use, namely Vodacom, MTN or Cell C. This was done by considering the five constructs used to measure relationship intention, namely involvement, expectations, forgiveness, feedback and fear of relationship loss. A focus group was used to determine which features related to cell phone network providers young adults consider when selecting a cell phone network provider. This data was used to develop a self-administered questionnaire, which was distributed among respondents studying at the Potchefstroom Campus of the North-West University in the North-West Provirice. A convenience (non­ probability) sampling method was used and a total of 315 respondents participated in this study. The distribution between the cell phone network providers was Vodacom (115), MTN (101) and Cell C (99). Initial data analysis revealed that 73% of respondents had high relationship intentions, while the remainder (26%) had low relationship intentions of forming long-term relationships with their respective cell phone network providers. By means of a factor analysis it was determined that the five relationship intention factors, namely involvement, expectations, forgiveness, feedback and fear of relationship loss, were valid and reliable to measure the relationship intentions of respondents. The results further indicated that respondents with a t"iigh relationship intention are more involved with thei r cell phone network providers and feared losing thei r relationships with their cell phone network providers more than those respondents with a low relationship intention. Furthermore, respondents from the different cell phone network providers do not view the five factors comprising relationship intention differently, but they do differ with regards to other factors related to cell phone network providers. It was found that the majority of respondents regard Vodacom (not necessarily the respondent's cell phone network provider) as the cell phone network provider with the latest technology, as being the quickest, having the best coverage, best handsets, coolest image and best service. The majority of respondents regard Cell C as being the cheapest and MTN as being the most expensive. Results also indicate that respondents' parents play an important role with regard to the choice of their cell phone network providers as the majority of respondents' parents initially chose the cell phone network providers and pay their cellular expenses. It is recommended that cell phone network providers should target young adults' parents with a view to gain a foothold in the young adult market. Furthermore, it is recommended that cell phone network providers should determine how their customers perceive them as compared with competitors in order to better position themselves and to improve communication with young adults. Most importantly, it is recommended that cell phone network providers should identify those young adults with high relationship intentions (those young adults who are more involved with and fear losing their relationship with the cell phone network provider more) in order to retain them by attempting to build long-term relationships with these young adults through dedicated relationship marketing efforts. Recommendations for future research include examining relationship intention with regards to other age groups (such as scholars and adults), other service industries and other geographical areas. Furthermore, the influence which young adults exert on decisions concerning cell phone network providers and the influence of parents on young adults' product and service choices, can be explored in future research by means of the family decision roles. / Thesis (M.Com. (Marketing Management))--North-West University, Potchefstroom Campus, 2010.
30

Motor telephony the practices and problems of regulating mobile telephony and driving /

Jessop, Glenn. January 2007 (has links)
Thesis (PhD) - Institute for Social Research, Faculty of Life and Social Sciences, Swinburne University of Technology, 2007. / Thesis submitted in fulfillment of the requirements of the degree of Doctor of Philosophy, Institute for Social Research, Faculty of Life and Social Sciences, Swinburne University of Technology, 2007. Typescript. Includes bibliographical references (p. 208-243).

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