Tight Bounds for Beacon-Based Coverage in Simple Rectilinear Polygons

Abstract

We establish tight bounds for beacon-based coverage problems. In particular, we show that $\lfloor \frac{n}{6} \rfloor$ beacons are always sufficient and sometimes necessary to cover a simple rectilinear polygon P with n vertices. When P is monotone and rectilinear, we prove that this bound becomes $\lfloor \frac{n+4}{8} \rfloor$ . We also present an optimal linear-time algorithm for computing the beacon kernel of P.