The dissertation is comprised of three papers. In the first two Chapters, I analyze the importance of competition, preference heterogeneity, and socio-economic/country-specific factors to explain the differences in penetration rates of mobile phone services across EU Member States. Chapter 1 presents a model of demand and supply for mobile phone services in which products are perceived as homogenous but consumers are heterogeneous with respect to their valuation of the services. Once a service is purchased, consumers (temporarily) leave the market. The parameters which govern the distribution of preferences are allowed to vary by country and will be estimated as part of the demand specification. The model matches the data well and is able to replicate the observed u-shape in the coefficient of variation in penetration rates over the sample period. Using the demand parameters, consumer acquisition costs are backed out and counterfactual experiments performed. I find that preference heterogeneity and differences in the cost of consumer acquisition explain most of the variation in penetration rates across countries. Competition and other control variables, such as the price of fixed-line calls, play only a minor role. In Chapter 2 I relax the assumption that firms are perceived as homogenous and model them as differentiated products. I incorporate endogenous population weights in a standard random coefficients logit model to capture changes in the demographic composition of potential buyers over time due to the (temporary) market exit of adopters. Compared to the results of Chapter 1, I find a larger role of competition and a smaller impact of the (net) cost of consumer acquisition in explaining differences in mobile phone services diffusion. In the third Chapter, I analyze the effect of a product introduction on labor supply. I demonstrate that it is possible to overcome many of the limitations associated with the lack of individual level purchase data by focusing on teenage labor supply and the introduction of video game consoles. I find that 16- to 17-year old male teenagers significantly increase their hours of work in the months prior to video console introductions beyond the usual male-female difference.

The ability of the mobile phone to reach and connect people like no technology before it, coupled with its productive potential to benefit private industry, governments, and the poor, makes it an extremely powerful tool for economic development – a tool that is worth investing in. Since their introduction, cell phones have demonstrated the ability to yield for the public good through improved information exchange and access to health care and financial services. In order to realize this potential, the private and public sectors must cooperate to improve regulations to encourage healthy competition and new capital investment while facilitating education in cell phone use.

While there are exemplary studies on the relationships between social networks and media such as television and the Internet, less is known about the social network consequences of mobile phone use during life-stage transitions. This study investigates the roles that mobile phones play in supporting the relationships of young people as they transition to and through their first-year of university in Toronto, Canada. Focussing on information practices during a transition that tests the resilience of support networks, this study queried the extent to which mobile phones play a role in keeping relationships intact, enabling students to maintain a sense of social cohesion and belonging. Data were collected from November 2007 to September 2008 through a longitudinal research design. Socio-technical concepts and network analysis techniques were applied to analyze the ways in which mobile communication is embedded in the everyday social life of young people aged 17-34. Set within the culturally-specific context of urban Canada, the data provided substantial evidence that mobile phones foster social cohesion within intimate relations but provide a more tenuous platform from which to nurture new relationships. First-year undergraduates have integrated the mobile phone into the way they engage with their social networks to a considerable degree, with commuter students experiencing additional tensions in negotiating relationships from home and on-campus. Findings showed that mobile phones were the devices of choice to mitigate feelings of loneliness, with deleterious consequences for the development of new relationships. Furthermore, the mobile phone was a key contributor to a rising sense of empowerment and autonomy for young adults as they negotiated identity transformations during their rite of passage into adulthood. Issues of trust and reciprocity in forming new relationships were mediated through a continuum of social media of which the mobile phone was the most intimate. Evidence of continuous access to social networks has broader implications for how mechanisms for coping with being alone and disconnection are acquired in this generation. Finally, observations of ritualistic interaction practices involving mobile phones may be theorized as small-scale evidence of larger societal shifts from collective constructs of community to that of networked individuals.

The dissertation is comprised of three papers. In the first two Chapters, I analyze the importance of competition, preference heterogeneity, and socio-economic/country-specific factors to explain the differences in penetration rates of mobile phone services across EU Member States. Chapter 1 presents a model of demand and supply for mobile phone services in which products are perceived as homogenous but consumers are heterogeneous with respect to their valuation of the services. Once a service is purchased, consumers (temporarily) leave the market. The parameters which govern the distribution of preferences are allowed to vary by country and will be estimated as part of the demand specification. The model matches the data well and is able to replicate the observed u-shape in the coefficient of variation in penetration rates over the sample period. Using the demand parameters, consumer acquisition costs are backed out and counterfactual experiments performed. I find that preference heterogeneity and differences in the cost of consumer acquisition explain most of the variation in penetration rates across countries. Competition and other control variables, such as the price of fixed-line calls, play only a minor role. In Chapter 2 I relax the assumption that firms are perceived as homogenous and model them as differentiated products. I incorporate endogenous population weights in a standard random coefficients logit model to capture changes in the demographic composition of potential buyers over time due to the (temporary) market exit of adopters. Compared to the results of Chapter 1, I find a larger role of competition and a smaller impact of the (net) cost of consumer acquisition in explaining differences in mobile phone services diffusion. In the third Chapter, I analyze the effect of a product introduction on labor supply. I demonstrate that it is possible to overcome many of the limitations associated with the lack of individual level purchase data by focusing on teenage labor supply and the introduction of video game consoles. I find that 16- to 17-year old male teenagers significantly increase their hours of work in the months prior to video console introductions beyond the usual male-female difference.

This thesis discusses the future of smart business applications on mobile phones and the integration of voice interface across several business applications. It proposes a framework that provides speech processing support for business applications on mobile phones. The framework uses Gaussian Mixture Models (GMM) for low-enrollment speaker recognition and limited vocabulary speech recognition. Algorithms are presented for pre-processing of audio signals into different categories and for start and end point detection. A method is proposed for speech processing that uses Mel Frequency Cepstral Coeffcients (MFCC) as primary feature for extraction. In addition, optimization schemes are developed to improve performance, and overcome constraints of a mobile phone. Experimental results are presented for some prototype applications that evaluate the performance of computationally expensive algorithms on constrained hardware. The thesis concludes by discussing the scope for improvement for the work done in this thesis and future directions in which this work could possibly be extended.

Are mobile phones the best vehicle for reducing gender inequality in the developing world? ICT experts champion the use of mobile phones to improve women’s lives, and various stakeholders have invested millions of dollars to launch mobile phone programs for women. Yet, given high female illiteracy rates, patriarchal societies, and other structural and cultural barriers in developing countries, many scholars contend that limited access to ICTs can perpetuate gender inequality. Rooted in the theory that women’s empowerment and equality are inseparable and necessary components for the realization of sustainable economic and social development, this paper aims to determine if stakeholders are jumping on the mobile phone bandwagon too soon by using a multivariate regression of cross national data to demonstrate whether or not mobile phones fall short of advancing women at the same rate that men develop.

Acoustic echo cancelation (AEC) composes a fundamental property of speech processing to enable a pleasant telecommunication conversation. Without this property of the telephone the communicator would hear an annoying echo of his own voice along with the speech from the other communicator. This would make a conversation through any telecommunication device an unpleasant experience. AEC has been subject of interest since 1950s in the telecom industry and very efficient solutions were devised to cancel linear echo. With the advent of low cost hands free communication devices the issue of non linear echo became prominent because these devices use cheap loudspeakers that produce artifacts in addition to the desired sound which will cause non linear echo that cannot be cancelled by linear echo cancellers. In this thesis a Harmonic Distortion Residual Echo Cancelation algorithm has been chosen for further investigations (HDRES). HDRES has many of those features that are desirable for an algorithm which is dealing with nonlinear acoustic echo cancelation, such as low computational complexity and fast convergence. The algorithm was first implemented in Matlab where it was tested and modified. The final result of the modified algorithm was then implemented in C and integrated with a complete AEC system. Before the implementation a number of measurements were done to distinguish the nonlinearities that were cause by the mobile phone loudspeaker. The measurements were performed on three different mobile pones which were documented to have problems with nonlinear acoustic echo. The result of this thesis has shown that it might be possible to use an adaptive filter, which has both low complexity and fast convergence, in an operating AEC system. However, the request for such a system to work would be that a doubletalk detector is implemented along with the adaptive algorithm. That way the doubletalk situation could be found and the adaptation of the algorithm could be stopped. Thus, the major part of the speech would be saved.

This thesis discusses the future of smart business applications on mobile phones and the integration of voice interface across several business applications. It proposes a framework that provides speech processing support for business applications on mobile phones. The framework uses Gaussian Mixture Models (GMM) for low-enrollment speaker recognition and limited vocabulary speech recognition. Algorithms are presented for pre-processing of audio signals into different categories and for start and end point detection. A method is proposed for speech processing that uses Mel Frequency Cepstral Coeffcients (MFCC) as primary feature for extraction. In addition, optimization schemes are developed to improve performance, and overcome constraints of a mobile phone. Experimental results are presented for some prototype applications that evaluate the performance of computationally expensive algorithms on constrained hardware. The thesis concludes by discussing the scope for improvement for the work done in this thesis and future directions in which this work could possibly be extended.

Aim: This study is part of a digital activation plan that was done for Sony Ericsson’s GreenHeart™ team in the fall of 2009. The investigation presents and discusses what Sony Ericsson and its 4 main competitors (Nokia, LG, Samsung and Motorola) have done within green digital marketing and how the subject was communicated on their webpages. The aim of this study is to: • To present and analyze consumer insights on ecologically-driven technology • To present and analyze the eco-marketing digital practices and strategies used by 4 competitive mobile phone brands • To propose a digital green marketing strategy for GreenHeart™ Method: This study consists of interviews with Sony Ericsson personnel, literature and web analysis that focus on the green initiatives of mobile phone manufacturers in the digital channel. Result & Conclusions: A main issue with green products is that consumers tend to find them not as good as non-green products. Consumer insight studies suggest that that the best way to communicate and promote green products is to focus on their direct benefits to consumers in comparison to non-green products, and communicate the green benefits only as a secondary message. This was also supported by theories such as Levit’s concept of “marketing myopia”, which describes a marketer’s tendency to focus on product features rather than consumer benefits. When analyzing the webpages of Sony Ericsson’s top 4 competitors, it was 3 evident that all 4 mobile phone manufacturers employed green digital marketing in quite a homogenous way. One striking similarity was that all brands have separated their green initiatives from the core of the website. It is a possibility that marketers have done this intentionally since consumers tend to associate green with lesser quality. In order for Sony Ericsson GreenHeart™ to stand out from the competitors, it was therefore suggested that green information should be integrated into the website and to communicate GreenHeart™ as a value-added product feature rather than a product in itself. Suggestions for future research: It is recommended to continue this research and to compare the findings from the mobile phone industry with other industries, such as the Fast Moving Consumer Goods (FMCG), where Green and Organic branding at a glance seem to have been developed strongly. It would be interesting to gain a perspective on the similarities and differences in the green marketing practices of different industries, but also to gain knowledge and inspiration on how green consumer electronics could be marketed in a more effective and integrated fashion. In this perspective, analyzing any variations between on- and off-line marketing initiatives would be interesting to see if the green message changes in a typical marketing mix. Moreover, it would be good to counter analyze the psychological mechanisms why, for certain industries such as food, green products are regarded as high quality whilst in another industry like electronics, green products are regarded as having lesser quality and business value. Contribution of the thesis: The most important finding of this study is that all the analyzed mobile phone manufacturers have many green initiatives. However, they are communicated separately from all other marketing and communication initiatives in the main digital channel. They tend to be set aside that consumers need to search for them, thus the messages are not delivered seamlessly. This makes it appear that green initiatives are being regarded as something obligatory rather than something that has true business value. Using Theoretical arguments on communication strategy from Levit and ClearWorks show how this, in reality, can be changed and be integrated with product marketing where it can generate a more significant business value

In this thesis the study mainly focuses on the trends in development of present-day mobile phones and provides a promising alternative for integrating various elements inside mobile phones. With the presence of a small ground plane protruded from the main circuit board of a mobile phone, the proposed antenna design is substantially different from the configuration of feeding the conventional internal patch or planar inverted-F antenna (PIFA), and the proposed antenna can be placed in close proximity to the RF shielding case in the mobile phone, with very small effects on the antenna performances. Thus, more flexibility in the integration between an internal antenna and other associated elements inside a mobile phone can be obtained. In addition, by making use of the space inside the shorting cylinder of the internal PIFA, which can be treated as a shielding wall, the lens module of an embedded digital camera or other possible practical modules can easily fit in the cylinder to satisfy the trends in development of the miniaturized and multi-function mobile phones.