What is a waveguide and what are its types?

Generally, if the frequency of a signal or a particular band of signals is high, the bandwidth utilization is high as the signal provides more space for the other signals to get accumulated. But the high-frequency signals can’t travel long distances without getting attenuated. We have studied the transmission lines that help the signals to travel longer distances.

A Waveguide

Microwaves propagate through microwave circuits, components and devices, which act as a part of Microwave transmission lines, broadly called as Waveguides.


A hollow metallic tube of the uniform cross section for transmitting electromagnetic waves by successive reflections from the inner walls of the tube is called as a Waveguide.

A waveguide is generally preferred in microwave communications. A waveguide is a special form of a transmission line, which is a hollow metal tube. Unlike the transmission line, the waveguide has no center conductor.

The Main Characteristics of A Waveguide Are

  • The tube wall provides distributed inductance
  • The empty space between the tube walls provide distributed capacitance
  • These are bulky, heavy, and expensive

Advantages of Waveguides

  • Waveguides are easy to manufacture.
  • They can handle very large power (in kilowatts)
  • Power loss is very negligible in waveguides
  • They offer very low loss ( low value of alpha-attenuation)
  • The microwave energy when travels through the waveguide, experiences lower losses than a coaxial cable.

Types of Waveguides

There are five types of waveguides. They are:

  • Rectangular waveguide
  • Circular waveguide
  • Elliptical waveguide
  • Single ridged waveguide
  • Double ridged waveguide

The above shown are the types of waveguides which are made hollow in the center and made up of copper walls. These have a thin lining of Au or Ag on the inner surface.