Phase-Noise Mitigation by Embedded Phase-Tracking Signals in 5G/6G

Abstract

Access to FR2 (high frequency bands) is essential for anticipated high-demand networking in 5G-Advanced and 6G systems. Unfortunately, phase noise is an unavoidable barrier, greatly limiting message reliability. Therefore, a low-cost solution is provided in which the transmitter (either base station or user device) transmits a special phase-tracking reference signal consisting of zero amplitude in one branch, and a predetermined non-zero amplitude in the other branch. For example, in QAM, the I-branch may be powered according to the maximum branch amplitude of the modulation scheme, and the Q-branch may have zero amplitude as transmitted. The receiver, on the other hand, generally measures a non-zero amplitude in the received Q branch due to phase noise, which rotates the I and Q branches into each other. The receiver can then determine the phase rotation angle precisely by measuring the non-zero amplitude in the Q branch, negating phase noise at negligible cost.

Dependencies are inferred from the claim text.