In this lesson,
we're going to explore some different types
of wireless antennas.
Antennas are a critical component in our wireless
communication systems
because they dictate the directionality
and range of the signal that's being transmitted
by your wireless access points
and other wireless networking equipment.
Wireless antennas are simply devices that are designed
to send and receive radio frequency signals,
and the type of antenna chosen
for a wireless system is going to greatly impact the quality
and efficiency of the wireless
communications that it can support.
Therefore, it's really important
to understand the different types of wireless antennas
that are out there,
including omnidirectional antennas,
unidirectional antennas,
and Yagi antennas,
as well as their different characteristics
and use cases to better be able
to optimize your wireless network's performance.
Now first, we have omnidirectional antennas.
Omnidirectional antennas are antennas that are designed
to transmit and receive wireless signals
in all directions equally.
This makes omnidirectional antennas great
for covering a broad area
with a relatively uniform signal strength
being transmitted out in all directions.
Commonly, you're going to find
that omnidirectional antennas are the default type
of antenna that's used by wireless access points
and wireless cards in your devices,
as well as in mobile hotspots
and wireless public networks
like those found in coffee shops, hotels,
or convention centers.
Now, when it comes to providing wireless access
to every client from a centralized location,
your best bet is usually going
to be an omnidirectional antenna.
Now second, we have unidirectional antennas.
Now, a unidirectional antenna is an antenna
that can focus all of its energy out in a single direction
to ride a more concentrated signal beam.
These unidirectional antennas are best used
when the majority of your signal needs
to be directed towards a specific area,
or when trying to reach a more remote location
from a centralized location.
You're often going to find unidirectional antennas are used
when you're creating a wireless point to point connection,
such as when you want to link two buildings on a campus
together or if you want to extend your internet service from
your main house to a smaller building
on the other side of your property.
For example, one of my friends owns a decent sized piece
of land up in Maryland that contains his home as well
as a barn about a half a mile
behind the house that he uses
to put his horses in.
Now the barn has electric run to it,
but no one had ever thought to run copper
or fiber cabling out to the barn to provide some level
of internet connectivity.
Now, my friend wanted to have a setup
where a wireless security system could be placed in the barn
so he could check on his horses in the middle
of the night if he needed to.
But to do that, he needed to add an access point to
that barn and create a connection back to the main home
where his network and internet service was coming from.
Now, since he didn't want to dig a half mile long trench
and bury a fiber optic cable to carry
that network from his house to the barn,
he instead bought two unidirectional antennas,
installed one of them on the backside of his house
and pointed it towards the barn,
and then installed another one on the front of the barn
and pointed it towards the house.
And this created a wireless point-to-point network
between the house and the barn.
And then he was able
to connect a unidirectional wireless access point
to the cable connected
to the receiving unidirectional antenna,
and the wireless access point was able
to receive full wireless coverage in
and around the barn once
it from that unidirectional antenna.
So when it comes to unidirectional antennas,
remember that they're suitable
for long and narrow coverage areas,
or when the signal needs to be strong in one particular
direction such as in a long corridor,
a point-to-point network,
or when you're targeting a specific area
over a larger distance.
Third, we have Yagi antennas.
Now, a Yagi antenna is a specific type
of directional antenna that can provide high signal gains
and uses a narrow beam width.
Yagi antennas are excellent
for long distance communication in a specific direction
and are often used in remote areas to connect
to a far off cell tower or for a television transmitter.
The design of a Yagi antenna consists
of multiple parallel elements in a line
that make them highly efficient
for picking up signals coming from the direction
in which they're pointed at.
Now, when you think of a Yagi antenna,
they're very similar to a unidirectional antenna.
In fact, there's a specific type of unidirectional antenna.
Basically, a Yagi antenna should be your go-to choice when
you need to capture and segment signals over long distances
or to form a specific fixed location,
such as establishing a link between a remote building
and the main network infrastructure,
or connecting to a distant ISP tower
for your internet service.
So remember, when you're choosing the right antenna,
this is going to be dependent on your specific needs
of your wireless system that you're going to be
designing and installing.
Your decision to use an omnidirectional, unidirectional,
or a more specific type of unidirectional antenna known
as a Yagi antenna really does hinge on your particular
requirements for your wireless network,
as well as the desired coverage area,
desired signal range,
and the physical environment
that you're going to be operating within.
By selecting the appropriate type of antenna,
you're going to be able to ensure that your network delivers
strong and reliable connectivity.
It's going to be tailored to the needs of your users
and the spatial constraints of your installation.
By using the right antenna,
you can not only enhance the performance
of your wireless network,
but you can also significantly
improve the user experience by providing a stable
and efficient wireless communication system.