Conference Paper

Optimal design of energy-efficient HetNets: joint precoding and load balancing

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... We thus survey the most relevant ones. Several works have addressed the problem of joint precoding and user assignment, however, for the optimization of power and energy efficiency, e.g., [21], [22]. [23] considered a HetNet setup, where each cell consisted of several inter-connected BSs, focusing however on the different problem of joint precoding and BS clustering, for sum-rate maximization. ...
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... We thus survey the most relevant ones. Several works have addressed the problem of joint precoding and user assignment, however, for the optimization of power and energy efficiency, e.g., [21], [22]. [23] considered a HetNet setup, where each cell consisted of several inter-connected BSs, focusing however on the different problem of joint precoding and BS clustering, for sum-rate maximization. ...
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In this work, we investigate the problem of mitigating interference between so-called antenna domains of a cloud radio access network (C-RAN). In contrast to previous work, we turn to an approach utilizing primarily the optimal assignment of users to central processors in a C-RAN deployment. We formulate this user assignment problem as an integer optimization problem, and propose an iterative algorithm for obtaining a solution. Motivated by the lack of optimality guarantees on such solutions, we opt to find lower bounds on the problem, and the resulting interference leakage in the network. We thus derive the corresponding Dantzig-Wolfe decomposition, formulate the dual problem, and show that the former offers a tighter bound than the latter. We highlight the fact that the bounds in question consist of linear problems with an exponential number of variables, and adapt the column generation method for solving them. In addition to shedding light on the tightness of the bounds in question, our numerical results show significant sum-rate gains over several comparison schemes. Moreover, the proposed scheme delivers similar performance as W-MMSE with a significantly lower complexity (around 10 times less).
... CN (0, 1) be the coded independent information symbols for user k, transmitted from BS v. 1 Then, the desired signals for user k transmitted by BS v is w k,v s k,v , where w k,v ∈ C Nv×1 is the linear precoding vector for user k at BS v. The aggregated transmitted signal from BS v is ...
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