frequency@@1	frequency	recurrence	4
frequency@@1	frequency	regularity	3
frequency@@1	frequency	constancy	2
frequency@@1	frequency	occurrence rate	2
frequency@@1	frequency	rate	2
frequency@@1	frequency	repetition	2
frequency@@1	frequency	wave frequency	2
frequency@@2	frequency	signal	7
frequency@@2	frequency	wavelength	7
frequency@@2	frequency	frequency signal	6
frequency@@2	frequency	transmission	6
frequency@@2	frequency	amplitude	4
frequency@@2	frequency	radio frequency	3
frequency@@2	frequency	rf	3