elephant cage; Wullenweber antenna
Literally 'elephant cage', but also a nickname for the Wullenweber antenna, a large circular antenna array used for radio direction finding. The technical sense is domain-specific.
I stopped in front of the elephant cage at the zoo.
A huge Wullenweber antenna was installed at the base.
Compound of 象 (elephant) + の (possessive particle) + 檻 (cage). The antenna sense comes from the visual resemblance to an elephant enclosure.