An Efficient Power Allocation Scheme for Ad Hoc Networks in Shadowing Fading Channels

In this paper, a distributed power allocation scheme for wireless ad hoc networks in shadowing fading environments is proposed. Considering fluctuated SINR during the reception of long packets, especially in multimedia communications, outage probability is introduced as a QoS parameter. An optimization model is formulated to minimize total transmit powers with constraint conditions that outage probability requirement of each link is satisfied. We explore a near-optimal closed-form solution by exploration of power ratio factor at system capacity. The power allocation scheme is based on the solution. In the scheme, power ratio factor of each link can be determined independently. The inequity problem of the power allocation algorithms in incremental fashion is avoided. Meanwhile the scheme is more time-saving than those schemes in iterative manner. The scheme can be implemented on a time scale longer than that of shadowing fading. Thus network overload is alleviated. By numerical example, we verify a better performance of our power allocation scheme than its counterpart.