Le WiFi USB sticks have many peculiarities that distinguish them from each other and, without a shadow of a doubt, one of the most important to keep in mind is the Wi-Fi class that they can support. This characteristic is specified with a sequence of numbers and letters and is a way to denote the maximum transmission speed which can be reached within the network.
Keep in mind that, by "transmission speed", I refer to the data transfer between devices connected to the wireless network and not to the Internet speed as, in addition to the Wi-Fi class, there are other parameters (latency, noise, quality of signal, connection type, etc.) which may affect the quality of the Internet connection. Having made this important difference clear, here are the available Wi-Fi classes at the moment.
- 802.11b (class b) - allows a maximum data transfer rate of 11 Mbps.
- 802.11g (class g) - allows a maximum data transfer rate of 54 Mbps.
- 802.11n (class n) - allows a maximum data transfer rate that varies (depending on the device) between 300 and 450 Mbps.
- 802.11ac (class ac) - allows a maximum data transfer rate equal to or greater than 13 Gbps (depending on the technology).
You can find, on some Wi-Fi sticks, support for the “802.11 b / g / n / ac standard”: this means that the device is compatible with all the classes mentioned above. In all cases, the maximum transmission speed is also affected by the Wi-Fi class (s) supported by the router.
Another parameter to be carefully considered, in terms of speed, is the broadcast band data on which the key is able to operate. The most common is the broadcast band a 2.4 GHz, used by most of the Wi-Fi devices on the market but, in the last period, the band a 5 GHz: unlike the former, this is less subject to interference and allows for higher communication speeds, however it has a shorter coverage range than the 2.4 GHz band. Wi-Fi ac, for example, it works exclusively on the 5 GHz band.
To take advantage of the 5 GHz of the WiFi key, however, it is also necessary that the router is equipped with support for the aforementioned frequency (and that it is placed near the key): these routers are defined in jargon. router dual-band (o tri-band, when multiple 5GHz frequency bands are combined).
WiFi USB sticks can be equipped with either internal antenna that of external antennas. Devices equipped with internal antennas are certainly more "comfortable" (especially for transport) and less bulky, however they generally offer worse reception than external antennas. This last solution, in particular, can come in handy if the router signal, in the place where you intend to use the key, is not particularly strong. Finally, external antennas can be fixed o removable ("Detachable" or not from the key), e directional o omnidirectional (which receive / transmit signal with priority from one direction, or from all).
The power of the antennas is expressed in dBi, the gain in decibels compared to an isotropic antenna: in general the higher the dBi gain, the better the signal reception, however its quality can be influenced by many other parameters. In other words, it is a parameter to keep in mind when choosing your key, but not the only influential!
There are WiFi USB sticks for all tastes and needs: some have the classic shape of the sticks used to store data and are equipped with an internal antenna, others can be even smaller. There are also larger ones with external antennas, and still others can have "extravagant" shapes: real cans, spheres or even magnetic media equipped with antennas, to be attached to the case and connected to the PC via USB extension cable.
This type of "stick", among other things, offers you more freedom of positioning: for example, if you have a desktop computer, you are not forced to keep the adapter connected to the USB port on the back of the case (where perhaps the signal is not optimal), but you can use the extension cable to place it where it performs best.
Since this is a key that communicates with the computer via USB, it is also important to consider it USB standard with which these are able to operate. It is easy to conclude that, for best performance, it would be ideal to use a standard compatible key USB 3.0 (connector with blue band and data transfer speed that touches 5 Gigabits per second) instead of a key compatible with the previous one USB 2.0 (connector with white band, which can reach “only” 480 Megabits per second).
Again, it's critical to consider the computer you need to use your key on: plugging a USB 3.0 key into a USB 2.0 port, or vice versa, will degrade performance at the lowest supported speed.
When you connect a device to your computer, it may happen that it works without the need for additional drivers, as these are already included in the operating system. However, many Wi-Fi USB sticks require the installation of dedicated drivers so that they can function properly.
Therefore, in order not to preclude its efficiency, it is necessary to make sure that the key in question is compatible with the operating system installed on the computer, either directly (ie without the need to install drivers), or after installing compatible drivers.
So far I have listed the most "important" features that affect the operation of a Wi-Fi USB stick, but there are also other aspects to take into consideration to analyze in detail both the quality of similar devices, and the usefulness or not. in the various scenarios. I'll list the most important ones below.
- Safety standard - this is how the router generates the network key. To date, almost all Wi-Fi USB sticks are compatible with the standard WPA2-AES, the most used to securely encrypt passwords.
- WPS support - some routers allow you to securely connect to a wireless device by simply pressing a button on both. Some Wi-Fi USB sticks offer support for this feature.
- MU-MIMO support - this technology allows a wireless device to manage the requests of multiple devices at the same time, improving the performance in the communication phase. Clearly, to take advantage of it, both the router and the WiFi USB stick need to be able to support it.
- Beamforming support - characteristic of the 5 GHz band networks, Beamforming allows to “automatically” intensify the signal on demand, in the direction in which it is temporarily needed most. To get the improvement via a compatible dongle, the router also needs to have support for this technology.
4G and Bluetooth keys
Before going into detail and explaining how to use a WiFi USB stick, I would like to clarify a fundamental aspect: there are also other devices capable of enabling a computer for "wireless" communication, with purposes other than those described so far, but aesthetically very similar.
For example, le 4G USB sticks they do not allow connection to Wi-Fi networks, but have a SIM slot that allows access to the Internet exclusively via cellular technology (2G, 3G or 4G). The same can be said for the Bluetooth sticks, which "only" allow you to add Bluetooth functionality on computers that do not natively have it.
How to use a WiFi USB stick
At this point, I just have to explain how to install and use a WiFi USB stick: in principle, what you need to do is connect the USB expansion key or cable to the appropriate port located on your computer, install if necessary i driver best suited to your operating system (which you can usually find on a supplied CD, or on the manufacturer's website) and restart your computer. Unfortunately, I cannot be more detailed on the driver installation procedure, since one may differ from the other: in principle, you have to proceed as you would for any other “installable” program on your PC.
Once the installation procedure is complete, you usually do not have to do anything else: you can connect to available wireless networks just like you would with a network card "included" in your computer. For example, on Windows, you can access the list of available networks by clicking on the dedicated icon (in the shape of a computer or Wi-Fi signal) located at the bottom left, while on MacOS and Linux you can find a very similar network indicator at the top right. If you need to take advantage of the exclusive features of your Wi-Fi USB stick, I also recommend that you install the proprietary software (often supplied by the manufacturer along with the drivers).
Once connected to the Internet, if you have a key equipped with external antennas and / or connected via a USB expansion cable, the last thing to do is to find, by trial and error, the position of the antennas or the entire device that can provide you with optimal performance. In this regard, I recommend that you carry out speed tests (I explained how to do it in my dedicated guide) at each "shift", and stop once you get the best result.
Which key to buy
Now that you understand perfectly how a WiFi USB stick works and that you have realized that it is a valid solution, you have decided to buy one that can satisfy your needs. Good choice! I anticipate right away that there are really something for all tastes and, above all, for all budgets.
How do you say? The information I gave you was very useful but you still need a little help to choose the one that suits you best? Then do not hesitate and consult my guide to buying the best WiFi key: I am sure that, in no time at all, you will find what you need.WiFi USB stick: how it works