  Next generation communication systems require accurate beam alignment to
counteract the impairments that characterize propagation in high-frequency
bands. The overhead of the pilot sequences required to select the best beam
pair is prohibitive when codebooks contain a large number of beams, as is the
case in practice. To remedy this issue, some schemes exploit information about
the user location to predict the best beam pair. However, these schemes (i)
involve no measurements whatsoever, which generally results in a highly
suboptimal predicted beam, and (ii) are not robust to localization errors. To
address these limitations, this paper builds upon the notion of radio map to
develop two algorithms that attain a balance between the quality of the
obtained beam pair and measurement overhead. The proposed algorithms predict
the received power corresponding to each pair and measure just the Q pairs with
highest prediction. While the first algorithm targets simplicity, the second
one relies on a Bayesian approach to endow the prediction process with
robustness to localization error. The performance of both algorithms is shown
to widely outperform existing methods using ray-tracing data.
