Moxa ANT-WSB-ANM-05 Manuel D’Utilisation

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Understanding Industrial WLAN – IEEE 802.11

Different wireless applications use different frequencies to achieve their purposes. To make sure wireless 
devices work as expected, users need to choose the right antenna with the right frequency. For example 
using a 5GHz IEEE 802.11a application with a 2.4GHz antenna can weaken or even completely wipe out the 
signal.

In addition to the key antenna specifications outlined above, there are some very simple tips you can use to 
choose the right antenna for your wireless project.

For a fixed point-to-point connection, we recommend choosing a directional antenna. Rather than 
broadcasting their signals linearly, directional antennas form a Fresnel Zone (a spherical expansion of the signal 
waves) and increase signal strength. The increased signal strength ensures smoother data transmission and 
connection.

When facing an application that requires constant changing of locations, omni-directional antennas make 
a better choice. An omni-directional antenna emits waves equally in all directions so it is easier for moving 
objects with constantly changing angles and positions to receive signals.

A few applications require special types of antennas, such as a leakage antenna for collecting data along rail 
tracks. These are very special cases and the deployment and infrastructure costs can be very high.