Optimal Pilot-to-Data Power Ratio for Massive SIMO Systems
(English)Manuscript (preprint) (Other academic)
We consider a single cell single input multiple output (SIMO) system employing orthogonal frequencydivision multiplexing (OFDM). In such systems, setting the pilot-to-data power ratio (PDPR)has a large impact on the spectral and energy efficiency. In this paper we provide a closedform solution for the mean square error (MSE) of the received data as a function of thePDPR assuming Gaussian channels and minimum mean square error (MMSE) equalization.In numerical experiments we find that the MSE is a convex function of the PDPRand study the optimal PDPR as the number of antennas at the base station (BS) grows large.We find that the optimal PDPR heavilydepends on the number of antennas and the path loss between the mobile station and theBS. Specifically, as the number of antennas grows large, a larger portionof the total power budget needs to be allocated for pilot signals, especially for low pathloss users.
MIMO systems, channel estimation, power control
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-126936OAI: oai:DiVA.org:kth-126936DiVA: diva2:642617
QC 201309162013-08-222013-08-222013-09-16Bibliographically approved