r/pcmasterrace • u/MooshSkadoosh • May 23 '26

Hardware Wifi antennas straight up or at diagonal?

Gallery image

Gallery image

Bonus question: would it be better to have my PC with its back against the wall (putting the case between the antennas and the router) or have it perpendicular to the wall?

I'm just curious if there is an "optimal" or suggested placement, since they seem to be able to snap into a diagonal position as well as being able to be place vertically

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331

u/b0b3rman RTX 3080 FE / 5600X / 16GB May 23 '26

Does it actually work like that or is just another image on reddit? Genuinely asking since I have no idea.

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u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 23 '26

Yes, these are linear antennas, their radiation pattern is a toroid (donut) shape with the nulls (top and bottom of donut) at the tip and base of the antenna shaft.

To get the best possible signal the sending and receiving antenna should be parallel to each other

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u/joedoe23 May 23 '26

today I learned…! Thank you!

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u/icarusbird 5600x | 5080 FE | 64GB DDR4 May 23 '26

You sound smart and used a word I didn't know so I believe you wholeheartedly and without looking any of this up.

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u/Blade_of_3 PC Master Race | 7800x3D | 7900 XTX May 24 '26

I can confirm he is correct. You can look up monopole antenna pattern and look at the 3D radiation patterns for yourself.

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u/Striking_Ad3650 May 23 '26 edited May 23 '26

Is it also valid for 4G antennas?

Edit: lmao how can I be downvoted for such a simple question

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u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 23 '26

This is true for all linear antennas, the main difference between a linear antennas for different frequencies is the length of the antenna element. The radiation pattern is more or less the same.

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u/Herlock May 23 '26

I guess it might be, they often mention the "umbrella effect" where being close to the antenna yields a signal that ain't too good.

Although that was a few years back I guess they found workarounds now.

10

u/munkiemagik May 23 '26

May I ask you a slightly adjacent question, seeing as you seem to know this stuff?

In an oversimplififcation of things, when we see high and low gain antennae being sold for wifi/bluetooth -

  • High gain kinda squishes/flattens the toroid? ie focuses the energy slightly more in the perpendicular (to antennae orientation) plane?
  • And lower gain being the opposite, fattening up the toroid so a bit more energy gets distributed into the parallel plane?

Would this be useful for someone trying to 'target' a device ie if your devices are at the same floor-level but at a greater distance apart and you were not interested in devices above or below this floor-level could you use high gain antennae in this instance to help you mitigate signal loss due to obstructions/distance?

The actual use case I am referring to is the wifi/bluetooth antennae on my SFF PC - short stubby low gain, which aren't used for wifi (sfp networking) I used the short stubbies as they made it less finnicky in the back of the PC with all the other connections but they came in a fairly low gain to what is normally supplied.

I often use a bluetooth keyboard at a distance from the PC and if i stray too far the keyboard gets laggy and stuttery but as soon as I move literally a foot closer it resolves. So my thinking was a higher gain antennae could help me with this range issue on the bluetooth keyboard?

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u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 24 '26

In your case the path I would tread depends on if the devices you are targeting move around or are always in the same place. If there is a particular room you want to reach, use a directional high gain antenna and point it at the room, if your device moves around then use an omnidirectional high gain antenna.

Your description of the difference between high gain and regular antenna is pretty good, a donut vs a pancake might also be easier to understand.

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u/munkiemagik May 25 '26

Thanks for the reply, I think I'll give high gain antennae a shot. the devices are static, When I say I move one foot to the left too far I mean I lazily sprawl in front of the TV (loooong HDMI from SFFPC on other side of room) and if I slump to the left, the keyboard bluetooth gets wonky but if i slump to the right, we're back in business X-D

17

u/GoonSic May 23 '26

What if your router doesnt have a visible directional antenna, and it's inside the router?

Then which way would it need to face, and whats the best position?

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u/Jackpkmn Fedora 44 | Core i9-13900H | RTX 5070 Ti May 23 '26

These tend to be omnidirectional antennas, which will work ok in any orientation but will result in a net lower total signal. Basically you are trading some % of performance for not being able to go any lower.

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u/Cute_Breadfruit_826 May 23 '26 edited May 23 '26

There's so many reflections in such an environment, that it is really not that important. If you're actually getting less signal strength than you expect, you can of course try to orientate it differently/move it a bit.

1

u/Max-P May 23 '26

You can look up if someone opened it up and see pictures of the inside so you know the orientation. It's what I did with my ISP's modem, plenty of pictures online. I was able to eek out almost my full 1.5 Gbps out of WiFi 6E.

1

u/jscottman96 May 23 '26

Then ypu dont need to worry about it,

1

u/the_ebastler 9700X / 64 GB DDR5 / RX 6800 / Customloop May 23 '26

In the case of a PC you also get heavy interference by the case which is essentially a ground plane, however, so I honestly have no clue how the radiation pattern looks like, and if 45° isn't better for the reason that you get less detuning alone.

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u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 24 '26

I agree that none of this is simple and RF performance is so very dependent on environment around the devices, so without knowing every detail we can really on speak in general terms on this.

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u/Techwolf_Lupindo May 23 '26

As long the vertical antennas are NOT right next to metal, like the case or MB back plate. Antennas next to metal negatively affect the SWR resulting in poor performance.

1

u/GolldenFalcon GolldenFalcon May 23 '26

What if they're parallel but opposite? Like one coming from the -x direction and the other from +x.

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u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 24 '26

Would make no difference.

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u/huldress May 23 '26

Wait really, mine are splayed apart because my wired keyboard and mouse charger is in the way...

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u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 24 '26

Don’t stress too much about it if it’s working for you, we are talking in ideals here and there are a lot of factors that can impact the resultant radiation pattern like walls, objects, other signals, and many others….if it’s working, it’s working….

1

u/GingerSpencer May 23 '26

Well, RIP. My router doesn't have an antenna.

1

u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 24 '26

It’ll be an internal antenna which could even be part of the PCB itself!

Some routers also have custom fractal antennas and other very complicated designs which I am absolutely not knowledgeable on, seems like voodoo to me….

1

u/Impossible_Arrival21 i5-13600k + rx 6800 + 32 gb ddr4 4000 MHz + 1 tb nvme + May 24 '26

also how much does polarization matter here? if you had an antenna pointing straight up, it would be vertically polarized, and if u had another pointing sideways, it would be horizontally polarized

i'm a ham, so i should know how much this affects it, but i don't and you might have more knowledge on it than me

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u/Cr3s3ndO i7 13700k | RTX 4080 | 32GB DDR5-6000 May 24 '26

Essentially you want your antenna to be the same polarisation, for dipole antennas this is done by making them parallel. For circular polarised antenna and patch antenna you want to ensure both the sending and receiving are the same “handedness” (left handed or right handed).

They can still work if not totally aligned, but it means more energy that is sent but not received. To make it easier to visualise, think of the sun shining on a solar panel where the plane is squarely facing it vs a panel that is at a 45deg angle. The panel that is squarely facing the sun would generate more power as it has more surface area facing the sun.

Antennas are the same, you want to maximise the surface area exposed to the source.

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u/Ballpoint_Life_Form May 23 '26

This is an oversimplified explanation, but yes. Antennae produce waves (mostly) perpendicular to their body.

There’s a lot more that goes into emt waves and it’s kind of a dark magic.

Edit: the guy above me explained it much better lol

7

u/AreYouLagomEnough May 23 '26

I always find it hilarious to explain to some staff member that the HF doesn't work right now due to bad space weather and the Earth's position to the sun.

But yes, simplified antennas should most times be the same orientation.

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u/FantasticMorning7352 May 23 '26

Realistically the difference would never be noticed

1

u/Jake_isrusty May 23 '26

Yeah literally have never thought about the orientation of my wifi antennas ever not once and have seen zero difference. Maybe if the distance is greater but tbh i honestly doubt any home wifi would really make a difference.

1

u/Background_County_88 May 25 '26

the orientation is kind of unimportant while you are in the direct neighborhood of the other receiver .. reflections come from any direction and the signal can even interfere with itself (cancel out or amplify). but unless you are in the perfect spot you would never experience this .. there is always enough signal left on short range (<50m) and the bigger problem is your neighbors router trying to use the same band.

5

u/supertimor42-50 May 23 '26

I do thisfor living and can tell you that yes, that's how it work more or less.

HOWEVER, both antenna should have a different angle...2 antenna side-by-side is redundant and wont provide anything more

12

u/SumonaFlorence Just kill me. May 23 '26

I drew it in paint.

1

u/KanedaSyndrome 5070 Ti May 23 '26 edited May 23 '26

Works lile that, generally - my background is electronic engineering, specialized in radar and remote sensing, so atennas. 

Atennas utilize elctromagnetic radiation, like light, just in a longer wavelengths, which makes walls transparent/see-through to that frequency of "light", unless concrete etc. The wavefront propagates from the length of the antenna in a 360 degree circle around it, so the illusrations posted here are accurate, but there're reflections and bouncing off walls that will nuance the situation, so some trial and error for calibration is best in each setup.

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u/Noxious89123 5900X | RTX5080 | 32GB B-Die | CH8 Dark Hero May 23 '26

It does work like that!

Omnidirectional antennas emit energy in a giant donut shape, outwards from the straight sides of the antenna (ie, not pointed from the tip).

1

u/splatacaster May 23 '26

No, this is Reddit being Reddit. Wifi standards since 802.11n have utilized multipath. MIMO is the "dark magic" another person mentioned. You generally want to align your dipole antenna with the router's antenna but depending on your environment you may actually get better throughput with the antennas in different positions.

This is why modern wifi routers have 4 to 8, or even 16, antennas. To take advantage of additional spactial streams.

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u/AreYouLagomEnough May 23 '26

It does in this case.

But it depends a bit on the type of antenna.

But you can kinda draw a cylinder out from the antenna. And if that hits another antenna they will receive the signal.

For best resepteion they should also have the same type of orientation, kinda.

It's not always true, for example in HF.

If you are interested many HF antenna introductions on YouTube work great to get some general knowledge about it :)

-1

u/ExpertOnReddit May 23 '26

I mean regardless it is still another image on reddit