Capacity of wireless networks with heterogeneous traffic under physical model

The throughput capacity of wireless ad hoc networks is derived when the traffic is heterogeneous but the node distribution is homogeneous. For the heterogeneous traffic we consider two types of traffic in the network, namely, unicast and data gathering communications. There are k sources that send different data to a single node and the rest of n - k nodes in the network participate in unicast communications with a uniform assignment of source-destination pairs. Under the physical model, it is proved that the capacity of these heterogeneous networks is Θ(n/T_max), where T_max and n denote the maximum traffic for a cell and the number of nodes in the network, respectively. The result demonstrates that the capacity is dominated by the maximum congestion in any area of the network. More specifically, the network capacity is equal to Θ(√n/log n) for k = O(√n log n) and equal to Θ(n/k) for k = Ω(√n log n).