Impact of imperfect power control on splitting and capture-based fast distributed selection

Opportunistic selection aims to select a node that improves the overall system performance the most. Selection is challenging as the nodes are geographically distributed and have only local knowledge. Yet, selection needs to be fast in order to allocate more time to the data transmission phase that exploits the selected node´s services. In this paper, we analyze the impact of imperfect power control on a fast, distributed, splitting-based selection scheme that exploits the capture effect by allowing the transmitting nodes to have different target receive powers and uses information about the total received power to speed up selection. The scheme owes its speed to the use of different target powers that facilitate capture. However, imperfect power control makes the received power deviate from the target and, hence, affects performance. Our analysis quantifies how it changes the selection speed, leads to the selection of wrong node, or no node getting selected. We also quantify the effect of imperfect power control on the net system throughput and the extent of error beyond which power control is not useful.