We always come across this presumption of many about external WiFi antennas. Some people believe they provide better coverage or have a much higher transmission strength when placed alongside internal antennas, 

We dare say that this is not true. We will categorically say that both internal and external antennas come with their own individual bane and boon, strengths and weaknesses. They are what is making them suitable for many different applications or uses.  

What is meant by internal and external antennas?

Internal antennas, much like how its name suggests, are installed inside the device itself. Hence, they are not usually visible from the outside, so the user would not normally see them. 

For wireless devices such as computers, mobile phones, and other similar technologies, the best way to describe their internal antenna is they are completely dominant.

When it comes to wireless equipment in the form of modems, routers, and repeaters, you will still find a handful of independent vendors in the market today that are still making use of external WiFi antennas for them.  

There are many types of internal and external antennas in use nowadays, but when it comes to wireless products designed for home use, there are two almost exclusively:  

1. Inverter F
2. Dipolantene

What you’ll have with an external Wi-Fi antenna is a coverage that is doughnut-shaped.  

As for the control of an external dipole antenna, you can execute that in a directional fashion. So, provided that you position your antenna at a perfect angle, you can expect that they will give out a more reliable, stronger signal in a particular direction.

Controlling signals directionally tend to work best when done outdoors. Perhaps, we can attribute this to the fact that there are only a few obstacles outdoors that can block the signals. 

There are a handful of obstacles when inside an indoor space that makes MIMO or multipath technology, which makes it possible for signals to make use of multiple paths to the client (in a simultaneous fashion) tend to work okay as opposed to directional control. 

It will also work to the advantage of a multipath to minimize the blind zone.  

For external dipole antennas, their blind zone comes in 60 degrees extending upwards as well as downwards. This makes the typical dipole signal pattern take on the appearance of a huge doughnut. What does this signify in terms of signal strength? It is telling us that above floor signal strength as well as below the antenna itself tend to be much weaker.  

WiFi Coverage from Internal Wi-Fi Antenna is shaped like a ball (almost)

As for the internal PIFA antennas, what they usually provide is a pattern that can be best described as more of a spherical than round. It also tends to get stretched out in any direction. 

What shapes down the pattern here is the manner in which the grounding was carried out together with the circuit size board in the unit. So, it is safe to say that it is not completely spherical in shape, but even so, signals will still be distributed more evenly as opposed to an external antenna.