Wireless communications has gained great popularity over the past decades. The wireless medium has many unique characteristics, which create new challenges as well as new opportunities in the communication problem. This thesis is devoted to the study of the ultimate performance limits of wireless communications. We study the effects of correlation, cooperation and interference in [...]
Integrating video support into the new Woize SIP-client
With VoIP services becoming more and more popular and, even beginning to compete with the PSTN (Public Switched Telephone Network) in terms of prices and wide use, companies that provides this service has to evolve to keep their customers and be competitive. Woize Ltd. is one of these companies and as a mean to strengthen [...]
License protection for high-end software
The BSA’s (Business Software Alliance) global study shows that 35% of all packaged software in use 2006 was illegal. The estimated loss due to software piracy was 40 billion dollars. It is therefore important for software companies to protect their software against illegal usage. Önnerlövs Consulting AB has developed a program for the mining industry [...]
Congestion notification and rate-adaptation for real-time services in All-IP radio networks
This Master thesis investigates solutions for handling congestion in All-IP radio networks. A mixed traffic scenario including a video and voice conversation has been studied using an advanced radio network simulator. The preventive measures investigated in this thesis are a bit rate adaptation scheme together with a congestion detection and notification mechanism, for real time [...]
Proof of concept implementation of UMTS long term evolution
In recent years, mobile communication has evolved rapidly and demand for mobile devices with new and higher quality services is increasing. The existing 3G standard, Universal Mobile Telecommunication System (UMTS), is currently being upgraded with High Speed Packet Access (HSPA) to meet current demands. However, in the longer term this will not be sufficient. The [...]
Satellite Network, Design, Optimization, and Management
We introduce several network design and planning problems that arise in the context of commercial satellite networks. At the heart of most of these problems we deal with a traffic routing problem over an extended planning horizon. In satellite networks route changes are associated with significant monetary penalties that are usually in the form of [...]
Optimization of Contemporary Telecommunications Networks: Generalized Spanning Trees and WDM Optical Networks
We present a study of two NP-hard telecommunications network design problems – the prize-collecting generalized minimum spanning tree problem (PCGMST) and the design of optical networks with wavelength division multiplexing. The first problem, the PCGMST problem, involves the design of regional backbone networks, where a set of local area networks (LANs) need to be connected [...]
Electronic Mediation, Transformation, and Business Value: Three Essays in the Retail Auto Industry
This dissertation seeks to answer the following research questions: (1) what properties enable some organizations to generate more value from information technology (IT) than others? and (2) through what mechanisms do organizations generate value through IT? It examines the role of technology in value creation through three essays using three different aspects of organizational performance. [...]