A dimensioning framework for indoor DAS LTE networks

This paper aims to dimensioning the number of antennas needed to satisfy a Long Term Evolution LTE data rate requirement in an indoor Distributed Antenna System environment, DAS. The approach presented in this paper depends on using two assumptions. The first assumption transforms any general indoor building layout to an equivalent square layout with the same surface area. This equivalent square layout is subdivided into a number of smaller sub-squares where antennas are assumed to be located at the corners of these sub-squares. The second assumption assumes that received power at any point inside the layout is dominated by antennas located at the corners of the sub-square where this point falls. The dependency of each sub-square area and the power assigned to the antennas at the edge of the sub-square on the number of antennas is used in the paper to find the number of resource blocks necessary to satisfy the location with worst coverage inside a given sub-square as a function of the number of antennas. The paper provides an approach to use this relation to derive the number of antennas required for the entire layout. Numerical results show that the number of antennas derived using the proposed approach presents an accurate estimation for the required number of antennas in a general non-square layout and without any assumption on the power calculation.