Paper Info
Title
Superimposed Pilots are Superior for Mitigating Pilot Contamination in Massive MIMO - Part I: Theory and Channel Estimation.
Abstract
Superimposed pilots are introduced, in this two-part paper, as an alternative to time-multiplexed pilot and data symbols for mitigating pilot contamination in massive multiple-input multiple-output (MIMO) systems. In this part of the two-part paper, a non-iterative scheme for uplink channel estimation based on superimposed pilots is first proposed and an expression for the uplink signal-to-interference-plus-noise ratio (SINR), at the output of a matched filter employing this channel estimate, is derived. Based on this expression, it is observed that the quality of the channel estimate can be improved by reducing the interference that results from transmitting data alongside the pilots, and an iterative data-aided scheme is also proposed that reduces this component of interference. Approximate expressions for the uplink SINR are provided for the iterative data-aided method as well. In addition, it is shown that a hybrid system with users utilizing both time-multiplexed and superimposed pilots is superior to an optimally designed system that employs only time-multiplexed pilots. Numerical simulations demonstrating the superiority of the proposed channel estimation schemes based on superimposed pilots and the accuracy of the approximations are also given in this part.
Year
Venue
Field
2016
arXiv: Information Theory
Uplink channel,Expression (mathematics),Control theory,Communication channel,MIMO,Interference (wave propagation),Matched filter,Hybrid system,Mathematics,Telecommunications link
DocType
Volume
Citations 
Journal
abs/1603.00648
1
PageRank 
References 
Authors
0.35
19
3
Name
Order
Citations
PageRank
Karthik Upadhya1244.54
sergiy a vorobyov21563113.46
Mikko Vehkaperä310315.36