The Research Of Transmission Capacity Of Ad Hoc Networks

The capacity is an important parameter to measure the performance of Ad Hoc networks. In the year 2000, Gupta and Kummar did research on the transport capacity and Throughput of Ad Hoc networks. This is a breakthrough in this area. After this, many other authors did further research on the capacity. However, the capacity can't be calculated with the approximate expression in most situations. So, as an intuitive description, simulation should be studied carefully.At the same time, in recent years, due to the scarcity and poor utilization of spectrum, people are beginning to consider the possibility of permitting secondary (SR) networks to coexist with licensed primary (PR) networks, which is the main driving force behind the cognitive radio technology. The key point of this article was to analyze the capacity for both single and overlaid Ad Hoc networks through simulation. The main work of this article is as follows:(1)Simplify the simulation method:we come up with an easy way to simulate the outage probability through calculating the optimal simulating radius.(2)Simulate outage probabilities on various Ad Hoc models: Simulating outage probabilities under the simplest model,Rayleigh fading model and the Channel Inversion model with the simplified method, and prove those calculation results are correct.(3)Come up with the simulation method of overlaid Ad Hoc networks:based on the simulation of single networks, we come up with the method to simulate the transmission capacity of overlaid ad hoc networks. Then we analyze the influence of the node density and channel model.(4)Put forward an easy way to calculate the bounds of capacity under Channel Inversion model:by comparing the characteristic functions of the normalized interference, we can get the upper and lower bounds of Channel Inversion model if we change some parameters. This method is proved to be correct by comparing our results with the existing ones. But it is much easier to handle.