Patent ID: 8259024

Claim:
A radio wave receiver comprising: an antenna structure including a rod-like core of a magnetic material and a coil wound around the core; a case encasing the antenna structure therein; and a pair of external magnetic members each made of a magnetic material of a permeability similar to that of the core, each external magnetic member being received in a respective one of a pair of cavities provided within the case, and each cavity being adjacent to a respective end of the core such that the core is magnetically coupled to the respective external magnetic members; wherein each of the pair of external magnetic members is disposed in the respective one of the pair of cavities axially outward of each end of the antenna coil so as to extend away from near outside the respective end of the core beyond a first line parallel to an axis of the core and passing through a center of the case, but beyond the first line each of the pair of external magnetic members does not further extend toward the other beyond a respective one of two second lines that are orthogonal to the first line and pass through two points, respectively, on an inner periphery of the case where the first line intersects the case.