Antenna Gain and Radiation Patterns Explained


Antenna Gain and Antenna Radiation Patterns Explained

Antenna Gain?  What is it?  Gain is a key parameter for antennas that is a product of radiation directivity and electrical efficiency. To better understand antenna gain,  antenna designers utilize two dimensional, and three dimensional patterns to aid in proper antenna selection.  These patterns provide system engineers a visual of how a specific antenna radiates.
Antenna azimuth Plot
Antenna Elevation Pattern
The above diagrams (Figure 1 and Figure 2) represent two cuts of a three dimensional radiation pattern, one for Azimuth (horizontal) and one for Elevation (vertical). This particular antenna was designed to be Omnidirectional with a peak gain at 2.4 GHz.  What this means to the customer is that the maximum efficiency and gain is achieved at this specific frequency. The first diagram represents the azimuth pattern of the antenna. To better understand the azimuth pattern, imagine looking down at the top of the antenna. Figure 3 is a 3D version of the antenna’s azimuth radiation pattern to help see how the two correlate.
3d antenna pattern
The elevation pattern plot (figure 2) represents if you are looking at the antenna from the side. Figure 4 is the 3D plot to show how the elevation diagram correlates to the polar diagram.  Since it can be hard to see the gain drops near the elevation angle of 90 degrees, this plot is in wireframe.
Antenna 3d Wireframe Plot

Based on both the azimuth and elevation polar plots, a customer can determine where the antenna gets the best gain and select the most suitable antenna for their project. The example above shows an omnidirectional antenna with gain that is rather even at all azimuth angles. This will be drastically different from a directional antenna that will offer higher gain values that are concentrated in a particular direction. Stay tuned for our next #techtuesday where we will take a deeper dive into antenna patterns and further discuss antenna selection.

MP Antenna, LTD. is the exclusive developer and manufacturer of advanced Multi-Polarized antennas that are well-suited for a range of applications including public safety, wireless broadband systems, WiFi, WiMax, video monitoring systems, 3G, CDMA, GSM, PCS and LTE. The company’s product line improves signal penetration and connectivity in obstructed deployments providing increased data throughput, enhanced voice clarity and multi-path mitigation. MP Antenna’s products are protected under numerous US patents with many US and foreign patents pending. MP Antenna is privately held and designs and manufactures its products at their headquarters located near Cleveland, Ohio, USA.