noun, noun which may take the genitive case particle 'no'
ultra low frequency
Technical term for electromagnetic waves in the 300–3000 Hz range. Often used attributively with の.
超低周波の電波は水中通信に使われる。
Ultra low frequency radio waves are used for underwater communication.
Compound of 超 (ultra) + 低 (low) + 周波 (frequency). A straightforward technical term.