Effective capacity of multi‐unicast flows using network coded‐ARQ

Abstract

In this Letter, the authors consider a multi‐unicast flow wireless communication system with a retransmission scheme. The effective capacity (EC) is used as a performance metric in order to make use of the recurrence relation approach. They also take advantage of network coding (NC) as combined with automatic repeat request (ARQ) protocol (NC‐ARQ), for more robust communication. The authors' main contribution, in this work, is the derivation of the EC for M ‐user NC‐ARQ using only the opportunity of XoR‐ing M packets. They then, focus on a 3‐user system and derive the EC using the opportunity of XoR‐ing packets for 3 and 2 users. An interesting result is the fact that, contrary to expectation, as the number of users in a network that uses NC‐ARQ increases, the performance in terms of EC increases as well, depending on how the sender schedules and manages the retransmissions.