radio frequency

But dense forest and tree canopies made cellphones and conventional radio frequencies useless.

These satellite arrays have detected radio frequency waves from a supernova 11,000 light years away.

The meters use a longwave radio frequency to switch between peak and off peak rates, and can also be used to turn heating and hot water systems on and off.

The radio frequencies that would be used were secret.

A contracted helicopter team followed the radio frequency emitted by the collars and essentially chased the wolves down, sometimes netting them or darting them from the sky, according to Hunnicutt.