A lot of drones use FPV feeds ,and it doesn’t matter if it is a racer of a camera drone, all of them use some sort of FPV feed to get the images to the ground.
There are 3 major ways to do this:
- 2.4GHz analog
- 2.4GHz Wifi
Analog 2.4GHz was used in the cheapest drones, it works.. that’s it.
The distance you get is not great, and the image you get is not as good as you want. Basically this is the one you don’t want to have if you want to rely on FPV alone. that said this technique is losing ground quickly do to the digital brother.. WiFi
WiFi FPV is the standard when it comes to toy grade drones and cheaper hobby drones.
The technique is cheap and easy to build and doesn’t require extra hardware.
The drone is a hotspot, and you can connect your phone or tablet with an app to receive the images.
This way there is no need for extra screens, they can just add a phone mount to the transmitter and you’re good to go. sometime you can even control your drone with the phone as well, meaning there is no controller needed at all. that makes the drone even cheaper.
Downside of WiFi is that is has a short range, and there are a lot of factors that can disturb the signal (high power transformations, microwaves, other wifi networks, etc.
This is great for practising with FPV, and works great in an open field if you don’t require a lot of distance.
The one that is commonly used on a lot of drones of all shapes and sizes is the 5.8 GHz FPV.
With this technology racers can manoeuvre very accurately since there is hardly any lag. for camera drones this is also a great benefit, what you see on your screen is what happening, real time.
The quality is great, and the lag is almost none, but since the frequency is higher, the distance is lower, and that is what I want to explain now.
Apart from upgrading your FPV transmitter to a better one that has more transmitting power (mw) there’s quicker ways to improve the distance, by using a different antenna!
Of course, a more powerful transmitter will help improving the FPV feed, but it is more or less useless without upgrading your antenna. Since rules in most countries don’t allow more than 150 meters up and not out of line of sight I am not going to talk about height improvement, or more distance from your feed, I want to show that improving the signal for distances that are legal is sometimes needed as well. for some reason standard antenna’s are not always good. I have heard stories of people’s feed breaking up after only 40 meters.
A different and better antenna could solve this!
Once thing very important to know as well is dbi, read about it in this post
Antenna’s come in all shapes and sizes, I am going to discuss directional and omni directional antennas in this post.
Here is a picture of the difference between the 2
Directional antennas (example 2) generally give more range because all of the signals are transmitted in 1 beam. downside is that the transmitter has to be pointed to the drone most of the times ensuring the best FPV feed, this is because the coverage of the signal of narrow.
Omnidirectional antennas(example 1) have a better coverage, but don’t have the same range as directional antennas.
These antennas are the best you can use on drones.
A simple example:
With a directional antenna you have to point to the drone, so if you want to fly over yourself (for whatever reason) you would have to turn around as soon as you have flown over in order to maintain FPV feed.
With an omnidirectional antenna you can do the same trick, but you can use the fpv feed to fly back without moving an inch.
Normally drones have omnidirectional antennas fitted, for the above reason.
But the stock antennas are not as good as we want, and simply don’t give enough range.
This is where a simple upgrade can do so much good.
replacing the stock antenna for a mushroom, cloverleaf or array is the best way to go.
Especially Mushroom and cloverleafs are the best, and only changing the antenna on the drone could give instant improvement! (arrays cannot be used on the drone, only on the remote)
Changing your stock antenna on your drone is the best way to get instant fpv improvement.
A Cloverleaf is best suited for the transmitter (drone), and almost exclusively used for this purpose. It has an excellent radiation pattern and very low gain.
Cloverleafs are not as goodlooking as mushrooms, but some find them better.
Either way, both mushroom and cloverleaf are good. replacing the stock antenna with this should give you trouble free FPV.
Of course changing both antennas is always better, and there are also TX and RX sets for sale, replacing them both is the best option then, and even recommended!
There is only one thing that no antenna can solve, and that’s interference.
You can upgrade all you want, but if you fly close to powerlines for instance, you can still experience interference.
Flying close to built up areas even at 50 meter distance, you can experience interference. this is because WiFi also uses the 5.8 GHz band. Consumer WiFi at 5.8 GHz is a lower frequency, but it could cause FPV break up as well.
Apart from that, if you are flying in an open area you should see improvement straight away.
It might even go higher and further away, who knows.
Here are some links to antennas.