A minimum energy routing protocol reduces the energy consumption of the nodes in a wireless ad hoc network by routing packets on routes that consume the minimum amount of energy to get the packets to their destination. This paper identifies the necessary features of an on-demand minimum energy routing protocol and suggests mechanisms for their implementation. We highlight the importance of efficient caching techniques to store the minimum energy route information and propose the use of an 'energy aware' link cache for storing this information. We compare the performance of an on-demand minimum energy routing protocol in terms of energy savings with an existing on-demand ad hoc routing protocol via simulation. We discuss the implementation of Dynamic Source Routing (DSR) protocol using the Click modular router on a real life test-bed consisting of laptops and wireless Ethernet cards. Finally we describe the modifications we have made to the DSR router to make it energy aware.

This paper considers two-dimensional interference-limited cellular radio systems. It introduces the shotgun cellular system that places base stations randomly and assigns channels randomly. Such systems are shown to provide lower bounds to cellular performance that are easy to compute, independent of shadow fading, and apply to a number of design scenarios. Traditional hexagonal systems provide an upper performance bound. The difference between upper and lower bounds is small under operating conditions typical in modern TDMA and CDMA cellular systems. Furthermore, in the strong shadow fading limit the bounds converge. To give insights into the design of practical systems, several variations are explored including mobile access methods, sectorizing, channel assignments, and placement with deviations. Together these results indicate cellular performance is very robust and little is lost in making rapid minimally-planned deployments.

No abstract

No abstract

No abstract