Fingerprint Adaptation for mmWave Vehicular Communications Based on Trajectory Prediction

Abstract

Millimeter-wave (mmWave) vehicular communication brings new technical challenges on wireless resource management due to the sensitivity to blockages and the directionality property, as conventional beam alignment techniques suffer from large communication overhead. To enable fast base station (BS) association and beam alignment, we propose a lightweight online learning framework by embracing sparse representation (SR) and Gaussian process (GP). To obtain preliminary information of the transmission environment, fingerprint-based method is advocated for static scenarios, while its performance degrades in dynamic scenarios. To incorporate the influence of vehicle motion, we innovatively propose the idea of trajectory-aware fingerprint, which further triggers the following two designs: 1) Trajectory Prediction: We utilize GP to predict the trajectory of moving vehicles. Noticing the utility of the forecast information drops fast with the computational complexity, we propose a differentiated prediction framework to balance accuracy and model complexity to maximize such utility and 2) Fingerprint Adaptation: As the existence of infinite number of trajectories, we approximate a trajectory using grayscale image, and prove the influence of such approximation on throughput is limited. Then, given a predicted trajectory, SR is invoked to perform robust fingerprint adaptation that facilitating resource management. Finally, the simulation results demonstrate the superiority of the proposed framework.