MmWave channel estimation using sub6-GHz channel information

01 Jul 2016
Due to hardware constraints, millimeter wave (mmWave) channel is not directly accessible and hence estimating mmWave channel for beamforming is difficult. Further, sub-6 GHz and mmWave systems are envisioned to work together, so assuming the knowledge of sub-6 GHz channel is reasonable.  Hence, it is worthwhile to investigate how the channel at sub-6 GHz and mmWave relate. This is particularly important for high mobility scenarios like vehicular communication, where frequent beam-training results in significant overhead.
In this research, WNCG graduate student Anum Ali, Universidade de Vigo Professor Nuria González Prelcic and WNCG Professor Robert Heath developed two approaches to translate correlation information from sub-6 GHz to mmWave. The first approach interpolates/extrapolates the sub-6 GHz spatial correlation to approximate mmWave correlation. The second approach estimates the correlation parameters of sub-6 GHz and uses them to estimate mmWave channel. Further, the excess error incurred in mmWave channel estimation by using the correlation information that is translated from sub-6 GHz is quantified.
A part of this work was presented at the Information Theory and Applications workshop (ITA) in February, 2016, and is available online at:
An extended version is under preparation to be submitted to IEEE Transactions on Wireless Communications.
This research was partially supported by the U.S. Department of Transportation through the Data-Supported Transportation Operations and Planning (D-STOP) Tier 1 University Transportation Center and by the Texas Department of Transportation under Project 0-6877 entitled “Communications and Radar-Supported Transportation Operations and Planning (CAR-STOP)."