Effective capacity in multihop multi-rate adaptive cooperative networks under Nakagami-m fading

Effective capacity model defines a delay bound violation probability and quality of service (QoS) exponent that help determine QoS in a system as a wireless link model for time varying channels. In this paper, we examine the effective capacity of an adaptive cooperative multihop wireless network using adaptive modulation and coding, under Nakagami-m fading. We extend the effective capacity derivations to four hops in cooperative networks employing relays with no queues. Then, we examine the effective capacity performance via numerical analysis in direct transmission and relay-aided cooperative communication networks under various fading conditions. We demonstrate by numerical analysis that relay participation in cooperative communication considerably increases the capacity at stringent QoS demands. However, it is also shown that effective capacity is lower at loose QoS demands when more than one relay is used, due to increased total average frame lengths with more time slot resource usage.