Power estimation in LTE systems with the general framework of standard interference mappings

Abstract

We devise novel techniques to obtain the downlink power inducing a given load in long-term evolution (LTE) systems, where we define load as the fraction of resource blocks in the time-frequency grid being requested by users from a given base station. These techniques are particularly important because previous studies have proved that the data rate requirement of users can be satisfied with lower transmit energy if we allow the load to increase. Those studies have also shown that obtaining the power assignment inducing a desired load profile can be posed as a fixed point problem involving standard interference mappings, but so far the mappings have not been obtained explicitly. One of our main contributions in this study is to close this gap. We derive an interference mapping having as its fixed point the power assignment inducing a desired load, assuming that such an assignment exists. Having this mapping in closed form, we simplify the proof of the aforementioned known results, and we also devise novel iterative algorithms for power computation that have many numerical advantages over previous methods

Low Complexity Iterative Algorithms for Power Estimation in Ultra-Dense Load Coupled Networks

“…In the first numerical evaluation, we compare the performance of the standard fixed point iteration in (14), which is a property that we observe in Fig. 3a.…”

“…We show that even the standard fixed point iteration applied to the mapping derived here can offer a substantial improvement with respect to the computational effort and accuracy over the specialized approach in [10]. In the later sections, we estimate load and power of networks by computing fixed points of standard interference 1 Some results in this study have already appeared in the conference paper [14]. Unlike [14], here we present all details of the proofs, and we derive novel distributed algorithms for power estimation.…”

“…In the later sections, we estimate load and power of networks by computing fixed points of standard interference 1 Some results in this study have already appeared in the conference paper [14]. Unlike [14], here we present all details of the proofs, and we derive novel distributed algorithms for power estimation. A similar distributed scheme has been independently proposed in [15].…”

“…in future systems, which will further exacerbate the problem of intercell interference if appropriate mechanisms for interference coordination are not devised [1], [2]. This fact has motivated many recent studies to focus on the development of simple models to gain insights into properties of the interference coupling in wireless networks [2]- [14].…”

Traffic demand-aware topology control for enhanced energy-efficiency of cellular networks

“…Nevertheless, having fully loaded cells as in Assumption 5 is desirable because it has been proven in [25] that full load (i.e., ρ = 1) is optimal with respect to the transmit energy consumption (see also [26]). …”