1 research outputs found
Joint Uplink-Downlink Cooperative Interference Management with Flexible Cell Associations
We study information theoretic models of interference networks that consist
of K Base Station (BS) - Mobile Terminal (MT) pairs. Each BS is connected to
the MT carrying the same index as well as L following MTs. We fix the value of
L and study the per user Degrees of Freedom (puDoF) in large networks. We
assume that each MT can be associated with N BSs, and these associations are
determined by a cloud-based controller that has a global view of the network.
An MT has to be associated with a BS, for the BS to transmit its message in the
downlink, or have its decoded message in the uplink. We propose puDoF inner
bounds for arbitrary values of L when only the uplink is considered, and
characterize the uplink puDoF value when only zero-forcing schemes are allowed.
We then introduce new achievable average uplink-downlink puDoF values, and show
their optimality for the range when N \leq (L/2) and when we restrict our
attention to zero-forcing schemes. Additionally, for the remaining range, we
characterize the optimal downlink scheme when the uplink-optimal associations
are used. Finally, we show that the proposed scheme is information
theoretically optimal for Wyner's linear interference network.Comment: 36 pages, 5 figures, submitted to IEEE Transactions on
Communications, Nov. 201