Consumer Adoption of Bandwidth Intensive Applications and Its Impacts on Broadband Adoption

This dissertation investigates the capacity required by an internet application in tandem with the network connection type (dial-up or broadband). An internet user’s experience in accessing various types of applications with either high bandwidth or low bandwidth is examined in a consumer choice model of broadband adoption. A consumer implicitly values the time-saving benefits derived from a higher speed internet connection used to access a particular internet application, and compares those utility benefits to the higher price of high speed connection services in making the decision to shift to broadband or remain with a dial-up connection. We find that using broadband rather than dial-up to run bandwidth intensive applications presents considerable gains in the implicit value of time saved. Assuming that internet users are rational utility maximizing agents, a logit model is used to calculate the likelihood of broadband adoption as a function primarily of the nature/type of the internet applications (“elastic or inelastic”). While the empirical results are generally consistent with our hypothesis that consumers are more likely to subscribe to broadband if they regularly run applications that are bandwidth intensive, the results vary somewhat by model specification, and are potentially sensitive to controlling for endogeneity. Correcting for endogeneity remains the major challenge in extending this research. Research Question: What is the relationship between consumer valuation of the net benefits of using bandwidth intensive applications and the adoption of broadband internet? Hypothesis: The less a consumer requires bandwidth intensive applications; the lower is the likelihood of switching from a low level bandwidth internet service like dial-up to a high level bandwidth internet type like broadband. While this relationship may appear obvious, it has not been systematically investigated or measured, nor has its importance in affecting lags in broadband adoption been adequately appreciated

3G Wideband CDMA : packet-based optimisation for high data-rate downlink transmission

A third generation (3G) of mobile communication systems, based on Wideband CDMA, are intended to offer high-speed packet-based services. Network operators wish to maximise the throughput in the downlink of3G systems, which requires efficient allocation ofresources. This thesis considers the problem ofmaximising throughput in an interference dominated channel. Cooperative broadcasting is a theoretical technique to mitigate this problem. Its implementation in practical systems requires efficient resource allocati.on to maximise the thr(oughput whilst meeting system and user-imposed constramts. A resource allocation approach is presented for implementing cooperative broadcasting. Users are paired and a teclmique for allocating resources between the pair is developed. Then, a method for pairing the users is considered. Simulation results are presented, which show a throughput improvement over existing resource allocation approaches. The problem ofcontrolling the distribution ofrandomly arriving data to meet the resource allocation specifications is examined. A single-threshold buffer is proposed, which requires fewer calculations than an existing double-threshold buffer. Simulation results are presented which show a throughput improvement may be realised, greater than that which would achievable using other rate control schemes. Cooperative broadcasting may lead to transmissions to some users being allocated low power. When full channel infonnation is available at the transmitter, a water filling solution may be used to maximise capacity. However, when combined with buffer management, erasure may result. This erasure may be overcome using an erasure protection code. Such a code is examined. When combined with Turbo coding, ajoint detector may be used for providing error and erasure protection. Analysis ofthis detector shows a lower limit on the error rate, dependent on the probability of erasure. Simulation results show that using this approach the error rate is significantly improved. This code can then be used to increase capacity, whilst achieving low error rates.Imperial Users onl