Patent ID: 8902808

Claim:
A method for mitigating interference in a wireless backhaul network comprising a plurality of nodes, each comprising a transmitter and a receiver, and wherein the plurality of nodes of the network comprise a plurality of hubs of the wireless backhaul network, each of said plurality of hubs serving a plurality of Remote backhaul Nodules (RBMs), comprising the steps of: determining an appropriate power spectral density level, for each of the plurality of nodes at each of a plurality of tones, based on known scheduling assignments and frequency domain channel gains for each link, comprising: performing an iterative operation to find the power spectral density at each tone, on an individual tone-by-tone basis, or optionally, on a tone set-by-set basis; updating power levels of each node, at each iteration and at each tone or for each tone set; wherein performing the iterative operation comprises, for an initial power level or a power level of a previous iteration, and for an objective function based on scheduling assignments for each node at all tones or tone sets, iteratively optimizing a weighted sum-rate across all nodes, and wherein for an objective function comprising a proportional fairness function, the iterative operation comprises a sum-rate optimization defined by: max ∑ l , k ⁢ w D , lk ⁢ r D , lk n s . t . 0 ≤ P D , l n ≤ S D max r D , lk n = log ( 1 + P D , l n ⁢  h jlk n  2 Γ ( σ 2 + ∑ j ≠ l ⁢ P Dj n ⁢  h jlk n  2 ) ) Equation ⁢ ⁢ 2 where: N is total number of subcarriers; k is the scheduled RBM of the lth hub at the nth tone; h n jlk is the channel response between hub j and the kth RBM of the lth hub at the nth tone; h n jlk is the average channel response between hub j and the kth RBM of the lth hub; W D,lk is a respective weight; P n D,l is the power allocated for the lth hub at the nth tone; SINR n D,l is the signal-to-interference-plus-noise ratio at the scheduled RBM of the lth hub at the nth tone; and S D max is the peak power constraint imposed on each hub at every tone.