  In a companion paper, we characterized the optimal resource allocation in
terms of power control and subcarrier assignment, for a downlink sectorized
OFDMA system. In our model, the network is assumed to be one dimensional for
the sake of analysis. We also assume that a certain part of the available
bandwidth is likely to be reused by different base stations while that the
other part of the bandwidth is shared in an orthogonal way between these base
stations. The optimal resource allocation characterized in Part I is obtained
by minimizing the total power spent by the network under the constraint that
all users rate requirements are satisfied. When optimal resource allocation is
used, any user receives data either in the reused bandwidth or in the protected
bandwidth, but not in both (except for at most one pivot-user in each cell). We
also proposed an algorithm that determines the optimal values of users resource
allocation parameters. The optimal allocation algorithm proposed in Part I
requires a large number of operations. In the present paper, we propose a
distributed practical resource allocation algorithm with low complexity. We
study the asymptotic behavior of both this simplified resource allocation
algorithm and the optimal resource allocation algorithm of Part I as the number
of users in each cell tends to infinity. Our analysis allows to prove that the
proposed simplified algorithm is asymptotically optimal. As a byproduct of our
analysis, we characterize the optimal value of the frequency reuse factor.
