Optimal pilot pattern for time variant channels

In order to estimate a transmission channel, a typical wireless communications system multiplexes a fixed pattern of symbols known at the receiver within the data-symbols. In Long Term Evolution (LTE), these reference symbols can consume up to 14.2% of the total transmission bandwidth. In this work, we investigate an optimal pilot-symbol pattern design using a post-equalization Signal to Interference and Noise Ratio (SINR) framework. We show how to choose the distance between adjacent pilot-symbols close to optimally and how to distribute the available power among pilot- and data-symbols at the same time under time-variant channels. We confirm our analytical solution by means of simulation. Compared to a system with a fixed distance between pilot-symbols and unit power distribution, the proposed system configuration yields significant gains in terms of capacity.