Power Estimation in LTE systems with the General Framework of Standard Interference Mappings

TL;DR

This paper introduces explicit interference mappings for LTE power control, enabling efficient computation of power levels to achieve desired load profiles, thus optimizing energy use and simplifying existing proofs.

Contribution

The study derives explicit fixed point interference mappings for LTE power assignment, filling a key gap and enabling new iterative algorithms for power control.

Findings

Derived explicit interference mappings for LTE load-power relation

Developed novel iterative algorithms with numerical advantages

Simplified proofs of load and power relationship in LTE

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 from 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.