Abstract
The incremental relaying scheme is one of the most efficient strategies in relay networks, whose channel model is quite different from the typical cellular channel and amplify-and-forward (AF) relay channel. As very little knowledge about the second-order statistics of the incremental relay fading channel based on decode-and-forward (DF) protocol, the level crossing rate (LCR) and average outage duration (AOD) of the incremental relay networks based on DF protocol are studied in this paper. The expressions of LCR and AOD are obtained in the Rayleigh fading environments. This result can help us to calculate the fading frequency and severe degree of wireless relay channel, and properly selecting the transmission symbol rate, packet length and time slot duration.