  This paper investigates the problem of distributed medium access control in a
wireless multiple access network with an unknown finite number of homogeneous
transmitters. An enhanced physical link layer interface is considered where
each link layer user can be equipped with multiple transmission options. Assume
that each user is backlogged with a saturated message queue. With a
generally-modeled channel, a distributed medium access control framework is
suggested to adapt the transmission scheme of each user to maximize an
arbitrarily chosen symmetric network utility. The proposed framework suggests
that the receiver should measure the success probability of a carefully
designed virtual packet, and feed such information back to the transmitters.
Upon receiving the measured probability, each transmitter should obtain a user
number estimate by comparing the probability with its theoretical value, and
then adapt its transmission scheme accordingly. Conditions under which the
proposed algorithm should converge to a designed unique equilibrium are
characterized. Simulation results are provided to demonstrate the optimality
and the convergence properties of the proposed algorithm.
