1. A noise pattern acquisition device comprising: a geomagnetic sensor; a coordinate estimation unit configured to estimate current position coordinates representing a current position of the noise pattern acquisition device; and a geomagnetic noise pattern management unit configured to, when an abnormality occurs in a magnetic field strength detected by the geomagnetic sensor during movement of the noise pattern acquisition device, store a geomagnetic noise pattern in a recording medium in association with the current position coordinates estimated by the coordinate estimation unit when the abnormality occurs, the geomagnetic noise pattern being a pattern representing a time-series change of the magnetic field strength detected by the geomagnetic sensor, the time-series change of the magnetic field strength being caused by the movement of the noise pattern acquisition device.