  In this work, we investigate a slotted-time relay assisted cooperative random
access wireless network with multipacket (MPR) reception capabilities. MPR
refers to the capability of a wireless node to successfully receive packets
from more than two other modes that transmit simultaneously at the same slot.
We consider a network of $N$ saturated sources that transmit packets to a
common destination node with the cooperation of two infinite capacity relay
nodes. The relays assist the sources by forwarding the packets that failed to
reach the destination. Moreover, the relays have also packets of their own to
transmit to the destination. We further assume that the relays employ a
state-dependent retransmission control mechanism. In particular, a relay node
accordingly adapts its transmission probability based on the status of the
other relay. Such a protocol is towards self-aware networks and leads to
substantial performance gains in terms of delay. We investigate the stability
region and the throughput performance for the full MPR model. Moreover, for the
asymmetric two-sources, two-relay case we derive the generating function of the
stationary joint queue-length distribution with the aid of the theory of
boundary value problems. For the symmetric case, we obtain explicit expressions
for the average queueing delay in a relay node without solving a boundary value
problem. Extensive numerical examples are presented and provide insights on the
system performance.
