| Wireless networks, and in particular, ad hoc wireless networks, represent a rapidly emerging area of growth and importance in the communication industry which has attracted much attention in recent years. Wireless networks consist of a number of nodes which communicate with each other using high-frequency radio waves. Some of these networks have a wired backbone connected to base stations with only the last hop being wireless. Cellular telephone networks and WI-FI networks (802.11) are examples of this. Ad hoc networks are another type of wireless networks. They are formed by a collection of nodes without the aid of any base stations. Since there are no base stations to route data through, the data needs to be routed to the destination by using the nodes. Ad hoc networks have many attractive qualities such as ease of deployment and flexibility. It is necessary to know their potentials and limitations in order to make the future design more efficient and avoid trying to do the impossible/impractical.;However, a lack of base stations results in difficulties in modelling the performance of such networks. There have been some investigations into the performance of ad hoc networks. Several areas that have not been considered are investigated. The effects of node density and system bandwidth is explored. It is shown that the performance of an ad hoc network can vary between two regimes depending on the bandwidth and density of the nodes. Many network models assume a uniform distribution of nodes. The effects of non-uniformity (clustering) are also studied. It is shown that clustering introduces two regimes on throughput performance which depends on the size of the network. Finally, the performance of an ad hoc network utilizing directional antennas is investigated. It is shown that a large increase in performance can be obtained. This performance increase can counteract the interference-related performance degradation of ad hoc networks for network sizes with thousands of nodes. |
