Cooperative Multi-Channel Wireless Networks and Their Applications

Growing popularity of wireless networks calls for their continuous evolution and improvement. Wireless devices are expected to be constantly decreasing in size and price. Meanwhile applications and services provided via wireless networks are expected to increase in popularity. We envision a Future Wireless Network (FWN) to consist of a large amount of miniature inexpensive autonomous devices spread in various location (e.g. hospitals, hotels etc). Along with the miniature devices the FWN may incorporate a set of WiFi access points (AP) which provide users with local Internet access. This thesis addresses some of the challenges of the FWN design. We consider how a FWN should use its available resources to ensure their efficient utilization. We examine how the FWN should adapt to various load heterogeneities within the network. These heterogeneities may by in icted, for example, by the activity of the users or the network layout. We consider the necessity of the FWN to exhibit a certain degree of exibility that will allow the FWN to accustom to diverse requirements of possible application scenarios. And finnally we consider how users should control and fine-tune the performance of the FWN. Node cooperation serves as a foundation of autonomous wireless network design in general. The cooperation increases intelligence of the nodes, makes them more aware of each other's activities. Research presented in this thesis is divided into two parts. The first part considers cooperation between miniature devices of a FWN, where we address the FWN design challenges by applying explicit multi-channel node cooperation. In particular we focus on sensor environments for health-care applications, where the devices are equipped with only single half-duplex transcei- vers and could be either on-body (e.g. Body Sensor Networks) or environmental. The second part of the thesis considers the implicit cooperation between a WiFi AP and its users.