Channel Estimation with Limited Pilot Beams in Millimeter Wave Communications

Abstract

We propose a two-stage method for channel estimation to overcome the performance degradation from using the limited pilot beams. At the first stage, we perform beam search using a few wide beams to estimate angle of arrival (AoA) and angle of departure (AoD) based on open-loop method. Then, the receiver feeds this information back to the transmitter. At the second stage, using obtained AoA and AoD at the first stage, we design new narrow pilot beams and estimate the channel gain with these narrow beams. Simulation results show that the proposed scheme outperforms conventional schemes with the limited pilot beams condition.