Bandwidth vs signal strength: How to get the best internet connection for your device

Bandwidth vs signal strength: How to get the best internet connection for your device

Summary: This is fast, that's over there; does bandwidth or signal strength matter more? Here's what I discovered.


In a London brick Victorian flat, you tend to need more than one wireless access point. We have two: both 802.11ac, one from Netgear, one from Buffalo, both with 2.4GHz and 5GHz connections.  My Lumia 1020 sees the 2.4GHz radio in our access point with more bars than the 5GHz radio in the same AP. That's to be expected; the AP is in the next room and 2.4GHz has a longer range than 5GHz.

access points
Which access point is going to be faster?

But I found myself wondering which connection I should use. The 2.4GHz connection offers lower bandwidth, but with better signal strength; the 5GHz connection has higher bandwidth, but will the weaker signal strength mean I get the same or even a slower connection? I fired up the Network Speed Test app from Microsoft Research, tested the speed on one connection (running it three times in case of anything else on the network that might affect the results) and then logged on to the other connection and tried it again.

7 down
The 2.4GHz connection might have looked stronger but it was slower in use.

The results did vary between the runs, but both the average and peak results showed better bandwidth from the 5GHz connection, even with the lower signal strength; up to 18Mbps rather than between 7Mbps and 10Mbps. I saw the same speeds on the Lumia 1520 on the 2.4GHz connection, so the faster processor in the phone didn't affect the throughput, but it didn't see the 5GHz connection at all.

18 down
The 2.4GHz connection might have looked stronger but it was slower in use.

With that kind of a difference, if you have multiple access points or connections visible, you may want to run your own speed test to see which is faster.

Interestingly, Windows Phone tended to pick whichever network I had connected to last, whereas Windows 8 is more likely to switch if it finds a network it thinks has better bandwidth.

Notebooks and laptops have higher-powered wi-fi chipsets that give you more bandwidth than phones and tablets, so switching to a better connection may make more of a difference on a PC. Or maybe that connection managing logic is something that will move into Windows Phone in a future version, given that it's based on the same kernel.

These are the kinds of alignments that will get easier if Microsoft rationalises the number of Windows versions it creates.

Further reading

Topics: Mobility, Wi-Fi, Windows Phone

Mary Branscombe

About Mary Branscombe

Mary Branscombe is a freelance tech journalist. Mary has been a technology writer for nearly two decades, covering everything from early versions of Windows and Office to the first smartphones, the arrival of the web and most things inbetween.

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  • Nice!

    You should also take into account the channel you are using...maybe other access point(or even your own) of your neighbor 's are clashing with your 2.4ghz signal hence slow throughput. There are less users of 5ghz access point so channel clashes seldom happens.(hard to explain if English isn't your first language:-))
    • good point but

      The routers will auto switch to a clear channel to avoid conflicts with other WiFi signals. That said in an apartment complex things will get jammed up especially if everybody has multiple access points setup and this can be problematic. You might also have a device with a guest connection which means the device presents two signals which will take two channels. It might be better especially in an apartment to disable the guest feature which will free up channels.

      Of course if your WiFi signal sensitive you'll need to double or triple your tinfoil. :-)
      • I dont set my router

        To switch channel automatically, coz i my experience, it doesn't my 2.4ghz i usually set my channel to 13 coz i noticed that most router defaults to 1,6,11.. But that's just me.
    • In 'Artford, 'Ereford and 'amphshire,

      'acking 'ardly hever 'appens?
  • Very crowded wifi spectrum

    There are no clear channels in our area; you can only see the top of the AP list but there are about a dozen Wi-Fi APs from nearby flats and houses. A lot of them are BT APs that offer a sort of guest connection that you can't disable (passing BT users get access). Running a spectrum analyser shows just how crowded it is... Possibly what we're seeing is the shorter range of 5GHz suffering less interference, but for me the interesting thing is the counterintuitive notion that you don't always want to pick the strongest signal ;)
  • If you want high bandwidth, use a cable

    If wi-fi (who coined this stupid term anyway?) doesn't deliver the speed you want or need, you can always try plugging in a cable connection. Then there's no conflict other than sharing what bandwidth your ISP provides with neighbours according to the contention ratio.
    • I've yet to find a phone with an Ethernet port :)

      And few tablets beyond Windows 8 models have either Ethernet or Ethernet capable USB. Wired connections are frequently faster but they're not available for all devices.
  • More data needed

    There are a lot of factors involved. Beyond simple signal strength, there is the actual bandwidth, the relation of that to your internet speed, and the biggest factor could be latency.

    Just to get it out of the way (because it probably doesn't apply in this case), if the 2.4GHz is a 54Mbps wireless and the 5GHz is 108-300Mbps, then a drop in signal will cut the maximum bandwidth. It's not a perfect 1:1, but you could theorize that 1/10th of the signal might only get you 5Mpbs on the 54 and 10-30Mbps on the other. From the screenshots, it doesn't look like it's that low, so with a decent signal, the 2.4 should still be above the 20Mbps internet I assume the writer has.

    Latency is probably the bigger factor. I'm not an expert, but I have read that latency is better on 5Ghz. If that is the case and there is some interference between both devices, the 5Ghz router would be able to resend lost data quicker than the 2.4. The latency, or lag time between starts/stops, would be better and increase the completion time which is calculated in the speed test results.

    The main and accurate point is that you try all options if you have more than one. Depending on your usage, latency could be a bigger or smaller factor. Granted, in most general usage, latency is an issue. Downloading one big file may be affected less by latency, but streaming content and average daily usage will be more dependent. In those cases, you may even be better to lose a Mbps or two for better latency. There are lot of variables. If you think you have as noticeable differences as is mentioned in this article (50% less speed than you expect), then obviously you should try different options.

    On a related note, I've had consistently bad results using this Network Speed Test app from MS. I've not done a lot of troubleshooting with it and it is fine for this type of side-by-side test, but has worked better for me.