A Comprehensive Study of Low Frequency and High Frequency Channel Correlation

Abstract

To meet the increasing throughput demand due to the proliferation of data-hungry services and applications, 5G technologies are adopting innovative solutions, such as using high frequency (HF) bands from 20 to 300GHz. While these bands provide more bandwidth and thus higher data rates, this comes at the price of higher propagation and penetration losses, making reliable communication more challenging in some scenarios. The characteristics of low frequency (LF) and HF bands are complementary, and multiband systems that combine the advantages of both types of bands are highly promising. In such a case, estimating the channel of one band given an prior channel measurement of the other band helps to reduce channel measurement overhead, provided the bands are correlated. In this work, we present a detailed study of the correlation between HF and LF bands. The existence of this correlation makes possible to reduce the overhead of expensive operations such as millimeter-wave beam steering to one third of its original time with an average loss rate SNR of less than 3dB.