RF

 

 

 

 

Wavelength vs Frequency 

 

The relationshipt between Wavelength and Frequency is determined by simple equation that you learned in high school physics.

 

Wavelength = Velocity / Frequency

 

This equation says

    i) When frequency is same, Wavelength gets longer as Velocity gets higher in vice versa.

    ii) When Velocity is same, Wavelength gets shorter as Frequency gets higher in vice versa

If we assume that the velocity of electromagnetic wave is same as the speed of light which is 3 x 10^8 m/s. Wavelength for some typical application can be calculated as follows.

 

Frequency (Hz)

Wavelength (m)

Wavelength (cm)

Comments

30 Mhz

10

1000

 

100 Mhz

3

300

FM Radio

300 Mhz

1

100

 

900 Mhz

0.333333333

33.33333333

Analog Celluar Phone

1000 Mhz(1Ghz)

0.3

30

 

2000 Mhz (2Ghz)

0.15

15

WCDMA

2400 Mhz (2.4 Ghz)

0.125

12.5

Bluetooth, WLAN

5800 Mhz (5.8 Ghz)

0.051724138

5.172413793

WLAN

15000 Mhz (15 Ghz)

0.02

2

Possible 5G Candidate (mmWave)

26000 Mhz (26 Ghz)

0.011538462

1.153846154

Possible 5G Candidate (mmWave)

70000 Mhz (76 Ghz)

0.004285714

0.428571429

Car Radar

 

If the electronic wave travel through special type of media (not free space), the velocity would change. According to the equation shown above, the wavelength would change as the velocity changes.

A common example is the case when the wave travel through a dielectrics. (See Dielectric page if you are not familiar with what it is and how it influence the velocity of electromagnetic wave)