Home of RF and Wireless Vendors and Resources

One Stop For Your RF and Wireless Need

electrical length vs physical length | difference between electrical length and physical length

This page compares electrical length vs physical length and mentions difference between electrical length and physical length.

The concept of physical length and electrical length is very useful in the RF and microwave circuit design. It is required to calculate physical length for different degrees of electrical length for dielectric substrate. Though the calculation is done using the RF calculators. Following equations are behind the calculations.

Electrical length

The electrical length of a cable can be expressed in degrees of phase shift. These units are used with smith chart required to do impedance matching.

To find electrical length, dielectric material properties are needed. First full wavelength(λ) for 360 degrees is determined using equations mentioned below.
λ = (1/frequency)*(Vf*3x108) ... Equation-1
Where, velocity of propagation (Vf) = 1/(εr)0.5

(Phase shift in degrees/360)*λ = cable physical length ... Equation-2
Here Phase shift in degrees is the electrical length.
λ = c/frequency,
c= 3 x 108 m/sec.

physical length

Let us calculate physical length of following data:
• electrical length= 45 degrees
• Frequency=500 MHz
• PTFE dielectric with Vf = 0.69

➨Physical length of cable = 5.137 cm

RF Wireless Tutorials

What is Difference between

difference between FDM and OFDM
Difference between SC-FDMA and OFDM
Difference between SISO and MIMO
Difference between TDD and FDD
Difference between 802.11 standards viz.11-a,11-b,11-g and 11-n
Bluetooth vs zigbee
Fixed wimax vs mobile
wibro vs mobile wimax
Microcontroller vs microprocessor

IoT Wireless Technologies

WLAN    ➤THREAD    ➤EnOcean    ➤LoRa    ➤SIGFOX    ➤WHDI   
Zigbee   ➤6LoWPAN   ➤Zigbee RF4CE   ➤Z-Wave   ➤NFC   ➤RFID   ➤INSTEON  

RF and Wireless Terminologies

Share this page

Translate this page