+1 vote
asked ago by
How does a quarter-wave dipole operate?
If a half-wave antenna is the shortest resonant length of an antenna, then how can a quarter-wave antenna function effectively?

Please log in or register to answer this question.

3 Answers

0 votes
answered ago by
Quarter-wave monopole antennas actually use a ground plane to ‘complete’ the other half of the antenna - so it still operates as if it were a half-wave resonant antenna. This means that a quarter-wave antenna should occupy a smaller footprint on a circuit board. It’s for this reason that they’ve become the most popular form of embedded antenna.

If you take a 916MHz application, a full-wave antenna would need to be just shy of 330mm long. A quarter-wave version would only need to be 87.2mm long. Surface mounted antenna manufacturers can coil this up across multiple layers, but they still require a ground plane of this length to operate as the other radiator. Without a ground plane of one quarter of the wavelength, the antennas efficiency would be compromised and to an even greater degree when operating at lower frequencies.
0 votes
answered ago by
This question is answered by attending lectures at the university or by reading professional books. If you ask Google about it you will also get an answer.
0 votes
answered ago by

How large of ground plane (mm2) is needed?   Is there a formula based on frequency?

Meet the moderators


Chris Tomlin
Antenna Applications Director, Antenova

Chris develops some of the smallest antenna modules and antennas in the world. He leads Antenova's R&D team and supports customers all over the world


Geoff Schulteis
Senior Antenna Application Specialist, Antenova

Geoff has 19 years' worth of antenna design and OTA measurement experience. He has an intricate knowledge of FCC and world carrier requirements.


Dan Dobransky
Senior Antenna Applications Specialist

Dan is an antenna integration specialist. He has a wealth of design-in and antenna development experience, which he uses to make sure our customer's products thrive


Antennas: The Comparison Guide

Find the perfect antenna for your project