How is Frequency Measured?

Answer: Frequency can be expressed as cycles per second or as waves per second. A reciprocal second (s-1) in SI units is also known as a Hertz (Hz), another name for one wave per second. The light’s speed is factor c.

Applying a test signal can be used to determine a device’s frequency response. For example, you could apply an impulse to the system and gauge its response, sweep a pure tone with a constant amplitude across the bandwidth of interest and measure the output level and change in phase concerning the input.