Size of back cover of smartphone - 60x100mm, so I can use 60x60mm plane ground (if it must be symmetric), or 60x100mm plane ground. Which size better in my case?
Thanks for reply.
6x10 is better then 6x6cm.
When you say minimum 10cm radius, do you mean diameter?
Thanks!
Yes,actually. Sorry about that
If I was to guess, I would say that priority should be given to the largest recommended size of ground plane and symmetry should be a secondary priority. In other words, I agree with @TB_RTK.
That said, if the recommended size is 100mm, and your available size was 70x120mm, then I would make the ground plane 70x100mm.
Why does the antenna need to be limited to smartphone size though? Do you plan to draw from smartphone battery and use cpu to power and control 4 small rotors on each corner for the first RTK-quad-phone-opter? 
Interesting,
So Iâm still seems unclear to me if symmetry is important, is circle better than a square shape? Also, what about the reflectivity of different materials copper, aluminum, nickel. Furthermore, what would be the difference between using say aluminum foil or a copper tape to save weight instead of a full metal plate?
To quote Tallysman
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Thank you for the quote didnât see that originally.
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So it appears that generally symmetry improves performance, as does wire routing (likely noise, and ability to reject) even if this is not notable to all users.
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Thickness doesnât really matter (seems to make sense, maybe slight/negligible losses)
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Material reflectivity generally does not matter (although I would say using more reflective materials obviously means lower loss and lower interference to components beneath)
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Recommended size is 10cm, clearly a higher gain. Although according to @bide this can change the optimal frequency range? I would say since it appears these are mere calculations that true real world testing would remain to be seen.
It looks like you have nailed down the principles! When you have to design your ground plane for sub-optimal conditions, then trial and error will tell you what is best.
@AllenCrawford @Allen_Crawford The 2406 has a built 56mm ground plane. So based on your prior info would you suggest this antenna still be placed on an additional 10cm plane??
Does the ground plane have to be⌠grounded? ie, electrically connected to ground (or negative terminal of a battery)?
@Fenrir I had the same question initially. No, it is just being used for reflection of the RF signal. No need to electrically ground it.
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I realize your point that it does not to be electrically grounded. Though in practice all antennas are grounded, which reduces noise. This may be noticeable noise or non noticeable, either way antennas that use coax cable (basically all antennas) use ground, because the shield of the coax cable is used s ground. So if you are making your own antenna my answer would be yes ground it if you can for best performance. No, it is not necessary to ground it though.
Has anyone experimented with a perforated or mesh groundplane? Iâm looking into mounting on a DJI phantom, and I think it will need good airflow though I doubt any kind of mesh could be balance airflow for a quadcopter with decent groundplane attributes.
Would this set up, in which the antenna is placed about 2 cm higher than the ground plane (a CD covered with aluminum foil) be appropriate? or must the antenna directly lay on the ground plane?
The performance of the antenna in your photo will be better than having no ground plane, but you should at least put the antenna directly on the foil.
- The space between the antenna and ground plane will hurt the performance.
- The ground plane being angled and not level with the base of the antenna will hurt performance.
- Your aluminum foil is OK.
- The wire can hang over the side of the ground plane, but is is better to drill a hole close to the antenna and push it through. Be careful not to kink the wire or bend too sharply as that will also hurt performance. The bend shown in your photo is OK, but do not bend it tighter than that.
Hello all,
I have 2 additional questions to that:
- In order to wire the cable below the antenna plate, one has to drill a hole in the plate, but wonât this hole hurt the performance of the Antenna?
- @bide, you asked at the very beginning of this discussion if a hemispherical plastic cover would hurt the performance of the antenna; has anyone some results with this design? I will have to do something similarly; I have an application where I want to catch my GPS station with a drone, therefore I need a hook above the antenna. Now, if the hooks is out of plastic (in the end something 3D-printed), basically I expect it to be transparent for the GPS antenna. If anyone has experince with that matter, it would be awesome if you would share. Otherwise I will make tests soon with this setup and can tell you my feedback afterwards.
Cheers
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Techinally drilling a hole in the ground plane makes it imperfect, but in practice it is not a big deal. Either let the wire fall over the edge of the ground plane or tuck it neatly though a hole. If you are obsessive about these things, you could change to a through-hole antenna, maybe like Tallysman TW3710.
In ideal design, the antenna is at the highest point. Any material blocking the sky view is detrimental, but it really depends on how much sky view is blocked; is the material transparent to the signal you are recieving, or does it attenuate the signal?
Consider offsetting the GPS antenna to the side and at similar height to the the hook which, I assume, will be at the center of gravity of your GPS station.
Unfortunately I saw these antennas to late which is why I bought the TW4721, so Iâll just stick to them now. But in that case it really seems to be far easier to just let the cable hang off the edge of the plate, I donât think it will cause such a bias. And if it does, a hole is drilled very easily. Thank you!
The material of which the hook is made will be PLA, and as far as Iâve read and been told in my lab, it is invisible to the antenna - but no one ever tried that. So that was the question, if someone already had some experience with covering the antenna with plastic. But in that case that will be something I will just test out in February/ March, and then come back to you guys.
Thank you!
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Why is the groundplane not connected to any part of reach? Shouldnât there be a connection to the negative pole of the antenna?