Antenna mods

[SSurogate2017]

According to marking on antenna in photo...it's from FPVLR.

. I used antena fpvlr

 

[Airbus350XWB]

I cant have 1.5w forced boost working, but with FCC boost, my distance increased significantly.. i live in CE country with wifi condensed city.. couldnt make it further than 13.500 feet before RTH. (Much better than 6.700 feet with stock CE without boost)

 

[drbulb]

Hello! New to the forum. I have a phantom 3 but plan to update to a Mavic soon. As an amateur radio operator I am very interested in the antenna mods being discussed and have some questions:
1. Can someone explain the function of the radio links? Obviously have control signals going out, and video and telemetry coming back. Which antennas are used for what and what frequencies do they use?
2. All of the antenna mod discussions focus on improving the 2.4 GHz link(s). The specs on the Mavic says the controller also uses 5.1-5.8 GHz. What is it used for and why no mention of antenna or boost improvement for this frequency?
ANY help would be appreciated. Thanks for your patience with a newbie!

 

[drbulb]

So is there a trim to adjust the antenna match? Any mention of using a SWR meter?
I will be interested at a future date in a more reliable signal so this isn't just me poo-poo'ing the products.

You sound like are or have been an amateur radio guy! Looking at the Mavic specs it says it also uses 5.1-5.8 GHz, but no one seems to mention that when talking about antenna mods. Any idea what frequencies are used where?

 

[Brojon]

You sound like are or have been an amateur radio guy! Looking at the Mavic specs it says it also uses 5.1-5.8 GHz, but no one seems to mention that when talking about antenna mods. Any idea what frequencies are used where?

My understanding is that the DJI drones with both can pick which band to use based on interference. They aren't used for different purposes.
Contrary to what you'd think the Phantoms apparently work better using the higher band. I was having video issues with my P4P and changed from auto to 5.8 on a suggestion and it really helped. I dunno if this translates to the Mavic - I haven't experimented with it yet.
My guess is it has to do with the wider bandwidth and power allotted by the FCC for 5 Ghz bands plus less activity/interference since most people do not use the 5 Ghz band on their routers even if it's available.

 

[Brojon]

Hello! New to the forum. I have a phantom 3 but plan to update to a Mavic soon. As an amateur radio operator I am very interested in the antenna mods being discussed and have some questions:
1. Can someone explain the function of the radio links? Obviously have control signals going out, and video and telemetry coming back. Which antennas are used for what and what frequencies do they use?
2. All of the antenna mod discussions focus on improving the 2.4 GHz link(s). The specs on the Mavic says the controller also uses 5.1-5.8 GHz. What is it used for and why no mention of antenna or boost improvement for this frequency?
ANY help would be appreciated. Thanks for your patience with a newbie!

If you read the whole thread you'd see that my primary concern is no test data at all.
My feeling is that there should be test data otherwise how do you gauge the merit of the mod.
That said 5.8 is roughly double so a 1/4 wave at 2.4 becomes a half wave at 5.8 - that's the antenna part.
These antennas also have built in amps which means they're pretty much stuck on 2.4 - reason is simple; a wide range of commercial 2.4 Ghz amps are made for that band since it's very common. Another concern is It unknown how duplexing is handled internally on these antennas.
I think they likely do have benefit given the anecdotal accolades, but I'm cautious given the lack of test data to back up the claims.

 

[lolo780]

Search posts by @beanbubba for some excellent tech info.

 

[frankj64155]

Let me know! I have a new better design!

On the left twice.

I'm in the market for 2 of the V2 in black if available. Let me know how to order. Thanks.

 

[beanbubba]

You sound like are or have been an amateur radio guy! Looking at the Mavic specs it says it also uses 5.1-5.8 GHz, but no one seems to mention that when talking about antenna mods. Any idea what frequencies are used where?

5gHz on the Mavic is only for the Wi-Fi radio (which nobody ever uses because of very short range support). All the real radio mods are in the 2.4 spectrum.

 

[beanbubba]

My understanding is that the DJI drones with both can pick which band to use based on interference. They aren't used for different purposes.
Contrary to what you'd think the Phantoms apparently work better using the higher band. I was having video issues with my P4P and changed from auto to 5.8 on a suggestion and it really helped. I dunno if this translates to the Mavic - I haven't experimented with it yet.
My guess is it has to do with the wider bandwidth and power allotted by the FCC for 5 Ghz bands plus less activity/interference since most people do not use the 5 Ghz band on their routers even if it's available.

FCC allows more power for 5ghz because the reach is shorter (on average ~25% less). 5ghz also has much less interference in urban areas. But if long range is your desire, 2.4 is the only way to go!

 

[Brojon]

FCC allows more power for 5ghz because the reach is shorter (on average ~25% less). 5ghz also has much less interference in urban areas. But if long range is your desire, 2.4 is the only way to go!

As they say the proof was in the pudding - 5.8 was vastly - and I mean vastly - superior on the Phantom.
I wouldn't have thunk it either but there it is...

 

[whizzing arrow]

Can someone tell me what type of antenna is it ? I've been searching for a long time on the internet and I can not find it I just know it is 2.4-2.5Ghz
looks like patch antenna but the elements are weird!

 

[beanbubba]

Can someone tell me what type of antenna is it ? I've been searching for a long time on the internet and I can not find it I just know it is 2.4-2.5Ghz
looks like patch antenna but the elements are weird!

View attachment 29243

With dual element panel antennas, the physical size will give you approximate coverage pattern and dBi gain. Is that unit around 7 inches across?

I would estimate that is probably in the neighborhood of a 100x100 degree beamwidth with 6dBi gain.

For reference, a 30x30/14dBi panel is around 13 inches across.

This is a plot for a 30x30:



This is a plot for a 100x100:

 

[whizzing arrow]

With dual element panel antennas, the physical size will give you approximate coverage pattern and dBi gain. Is that unit around 7 inches across?

I would estimate that is probably in the neighborhood of a 100x100 degree beamwidth with 6dBi gain.

For reference, a 30x30/14dBi panel is around 13 inches across.

This is a plot for a 30x30:

View attachment 29245

This is a plot for a 100x100:
View attachment 29246

Thank you for your reply,WOW thank you very much for the information very instructive The antenne size is 5x5.5cm

 

[Phxbird57]

The amp is for both transmit and receive. The amps help significantly with the proper antenna. It did help with those fpvlr yagi antenna, but there is a lot of interference resulting in poor video quality at times. I've had much better luck with the circular polarized antenna. I have RexUAV antenna which was intended for 3dr solo. It has amazing signal with the amps. I went out 54,200ft and total trip of of over 108,600ft in silicon valley and not once did I get low signal and video feed was perfect.

Nate by chase did you try any of the panel antenna's (CCP or even the maxx small panel),we are using for the P3 a/p drones. to see how they would work?

 

[Phxbird57]

lol, hey, unless they call you "stubby" that would be more than an inch

I stand on the rear bumper of my truck. gives me 2 more feet.

 

[beanbubba]

I stand on the rear bumper of my truck. gives me 2 more feet.

That's what she said

 

[CyberNate]

Nate by chase did you try any of the panel antenna's (CCP or even the maxx small panel),we are using for the P3 a/p drones. to see how they would work?

I upgraded to the 4Hawks XR with Sunhams 3W boosters, which is really the same as the MaxUAV panel for phantom series. Works even better than my RexUAV. It's a little bit on the big/heavy side but I can still hold controller with my ipad mini. If I use a larger tablet and tablet holder, it's too heavy.

I should add, I have tried the smaller MaxUAV panel and that one was not nearly as good as my RexUAV; however I may have gotten a bad panel. Others are having good success with it. Mine never worked right even with boosters.

 

[lolo780]

Liehuo 14dbi panel straight out of the box. I connected it to the left side port of my MaxxUAV Evolite, and left the Nanosync on the right side port. Home point is elevated ~100m.

The Nanosync will also give good signal at the distance limit, but the ccp is about 1 bar more HD. Didn't notice any difference on RC.

 

[SkyNinja]

Phxbird57,

I tried the small max panel both boosted and unboosted. Neither of them perform much better than stock. The larger Maxxrange panel antenna is bad ***, especially boosted. 90% of the time I’m flying use the Titan Cyclone, but if l really needed punches through a highly congested areas I use the Maxxrange panel It works the best for me and I own few different antennas.