# Test and Measurement World

## Test and Measurement World Measurements Section

One Stop For Your Test and Measurement Need

## What is frequency measured in | Frequency measurement

This page on describes unit of frequency measurement i.e. it mentions in what unit is frequency measured in. It mentions frequency measurement equipment or device.

The term frequency refers to number of cycles or periods of a waveform (either voltage or current) in a second. For example, if there are 5 periods in a second, it means frequency is equal to 5 Hz or Hertz.

The basic unit of frequency measurement is Hertz (abbreviated as Hz) or cycles/sec. The other units used for simplicity are KHz, MHz, GHz and THz. These units are used to measure frequency having larger values.

Following is the relationships between these units and Hz.
1 KHz (Kilo Hertz)= 103 Hz
1 MHz (Mega Hertz)= 106 Hz
1 GHz (Giga Hertz)= 109 Hz
1 THz (Tera Hertz)= 1012 Hz

### Frequency Measurement Equipment and Method There are various equipments used for frequency measurement as mentioned below.
• Oscilloscope, though it displays time on X-axis and amplitude on Y-axis. The real time oscilloscopes convert X-axis into frequency domain and provide the frequency measurement reading after proper frequency range is set.
• Frequency counter: It displays frequency reading in numerical digits as per resolution.
• RF Spectrum analyzer: It displays frequency on X-axis and power on Y-axis. The markers are used to determine the peak in the waveform after appropriate frequencies are set. The peak of the marker reads out value of the frequency.

The figure depicts common setup or method used for frequency measurement. As shown the output of the DUT is fed as input to the above mentioned frequency measurement equipment (any one out of three listed). During measurement, either frequency range or (Center Frequency, Bandwidth) is set in the instrument.

Following are the links to other useful measurements available on Test and Measurement World website.
Difference between EVM vs subcarriers and EVM vs symbols
Current measurement vs Voltage measurement
Inductance measurement vs Capacitance measurement
Difference between Power and Energy measurements
EMC measurement vs EMI measurement
Electric and Magnetic Field Measurements

### What is difference between or comparison between

Following links mention difference or comparison between various equipments:
comparison between VSG and VSA
DIfference between SNA ans VNA
Oscilloscope Bandwidth versus Rise time
Oscilloscope vs Logic Analyzer
Difference between Oscillscope types
Comparison between spectrum and network analyzer