Integrating mobile ad hoc networks with cellular networks

Traditionally, wireless systems are designed based on the centralized cellular network. Recently, however, a distributed wireless network model, mobile ad hoc network, has drawn significant research interest. The confluence of these two wireless network models and technology presents an opportunity for a new type of wireless network paradigm, which we call a hybrid wireless relay network. In this dissertation, we present research issues regarding hybrid wireless relay network.; First, we investigate hybrid wireless relay network architecture based on dual-mode terminal relay. We propose a novel integrated WWAN/WLAN two-hop-relay architecture that both enhances the system capacity of 3G cellular systems and extends the system coverage area of 802.11 terminals. The proposed two-hop-relay can be considered as a macro-diversity technique that utilizes temporal channel quality variation to increase system capacity.; Furthermore, to encourage cooperative relay in user terminals based hybrid wireless relay networks, inspired to design a novel incentive mechanism in such a network. The Nash Equilibrium concept of game theory is applied for the incentive scheduling mechanism design. We propose an incentive scheduler, which leads to cooperative Nash Equilibrium that all dual-mode terminals relay cooperatively.; To gain insightful understanding of hybrid wireless network system performance, we investigated the capacity regions of hybrid wireless relay networks. We formulate the network capacity based on a linear programming approach. The capacity models of four distinct hybrid wireless relay network architectures are developed. Some capacity model development issues regarding IEEE 802.11 based relay networks are also discussed. Numerical capacity results show the proposed capacity model adequately predicts the system performance of hybrid wireless relay networks.; In addition, we proposed another hybrid wireless relay network architecture based on fixed wireless relay routers rather than mobile user terminals. We investigate network planning and design to facilitate deployment and improve system performance. We also presented a multihop relay architecture called Adhocell and how system throughput can be enhanced through hybrid multihop relay.; Moreover, energy efficient design issues in hybrid wireless relay networks are investigated. The IP Paging architecture is proposed to improve energy efficiency in an Internet-connected hybrid wireless ad hoc network that consists of battery-driven mobile devices. Mobile devices can go into a dormant mode to save battery energy consumption when they do not have active data sessions. The proposed IP Paging architecture extends the IP Paging framework in Mobile IP based single-hop wireless cellular networks to hybrid wireless relay networks.; Lastly, in order to design a spectral efficient hybrid wireless network, we opt for joint design of the data link layer and the network layer. We investigate a hybrid wireless relay network architecture with a time slotted medium access protocol at the data link layer and with a probabilistic routing protocol at the network layer to achieve high spectral efficiency. Additional high-speed radio link installation to alleviate congestion around the Internet Gateway has also been shown to effectively improve network system performance.