Before you can even think about fixing a problem with Wi-Fi congestion or interference, you need to know what’s causing your network to misbehave.
Fortunately, there are a number of free applications that will help uncover the root of your problem, and more sophisticated RF devices for keen interference hunters.
A brilliant free tool for discovering precisely how many other Wi-Fi networks you’re competing with in your home or office is inSSIDer 2.
This lists every access point within range of your PC and is far smarter than the list provided by Windows’ Wireless Network Connection Manager for a number of reasons.
First, it lists a barrage of useful information about each access point within range, including channel number, the strength of the signal, and the make of the router itself.
Better still, if you leave inSSIDer running for a few hours, it will remember all of the access points that have been switched on/off during that period, not merely list the ones currently running as Windows does. So if your neighbours only switch on their (potentially interfering) routers during the evening, you’ll know about it.
The list of available networks can be sorted by channel number, so you can easily see how many neighbouring networks are sharing your channel. The amplitude and channel number of each access point are also plotted on a graph, allowing you to see who your noisiest neighbours are – in Wi-Fi terms, at least.
Using the graph shown below, for instance, it would make perfect sense to assign your router to channel 11, where none of the neighbouring access points would overlap, while channel 6 should clearly be avoided.
For those using dual-band routers, there are separate graphs for both the 2.4GHz and 5GHz bands, allowing you to find a suitable gap.
Another exceptionally useful free tool for large homes or offices is ekahau HeatMapper.
With HeatMapper, you can either upload a plan of your home/office/site, or effectively create one from scratch using the software. You can then wander around your office with your laptop, left-clicking the mouse as you walk from room to room or desk to desk.
The end result is a Wi-Fi heatmap of your premises, allowing you to see which parts suffer most from Wi-Fi congestion and make an informed decision about where to locate your router or clients.
If, for example, the desks next to the windows in your office are drenched in red, you might want to move the hot-desks for your laptop-toting staff into a more central position.
If, however, the heatmap reveals your neighbour has their router next to a party wall, it might make sense for you to avoid plugging in your router there, or at least make sure you’re using non-overlapping channels.
However, both inSSIDer and HeatMapper have one unavoidable weakness: they rely on your PC’s wireless card and are thus incapable of detecting any non-Wi-Fi interference. Other Wi-Fi traffic may actually be the least of your problems.
To detect and eliminate other sources of RF interference, you’ll need a dedicated piece of kit. MetaGeek’s Wi-Spy spectrum analysers, along with the company’s Chanalyzer software.
These USB dongles not only detect neighbouring Wi-Fi networks, they also map and measure other RF interference, allowing you to make an informed decision on the placement of your router and which channel to use.
Although software such as HeatMapper and Chanalyzer will help you find the least interference-prone areas to park your router, there are some more general dos and don’ts to maximise performance.
Avoid placing the router near any large metal objects, such as filing cabinets or radiators, that could shield or bounce the signal in unpredictable ways. Also avoid placing it near any other electrical equipment, such as your television set or hi-fi equipment.
Sky engineers have told us that Sky+ boxes are particularly sensitive to nearby wireless routers, not only potentially interfering with your Wi-Fi signal, but also with the normal operation of the PVR itself.
In a home, where you’ll likely want decent Wi-Fi coverage in every room, try to place the router as centrally as possible. Don’t leave the device on the floor – not only does this give the signal further to travel to upstairs rooms, but modern routers (especially those with LCD panels) can become rather hot, and the last thing they need is the extra insulation of your plush living room carpet.
The main reason people tend to shove their routers out of sight in an awkward, signal-restricting part of the house is because they’re not exactly attractive ornaments.
A router with three external aerials sticking out like sore thumbs is hardly a contender for mantelpiece space alongside the vase you bought back from Sicily, which is why the router manufacturers are getting smarter with their antenna design.
For example, D-Link’s forthcoming range of high-end routers and boosters will come with six internal, rotating antennae that allegedly make up for the lack of external antennae by focusing the signal towards the wireless devices in the home.
So, if you’re using your laptop in the living room, and one of the kids is downloading an app on their iPhone in their bedroom, each of you will have three antennas pointed in your direction.
“It’s an amalgamation of various technologies that allows us to focus the energy of the router,” said D-Link’s Roger Tao. “A classic router is 360 degrees – it’s omnidirectional, it isn’t focusing its power. If I’m broadcasting to my neighbour’s house, he’s going to get some of my power.”
D-Link claims this SmartBeam technology will typically offer a 20% performance boost over a traditional router.
Even without significant interference, it can still be difficult to get a Wi-Fi signal to travel reliably from one side of the home or office to the other.
Unless you live in a radiation-shielded, open-plan bunker in the Outer Hebrides, you can forget about achieving the 300Mbits/sec+ speeds quoted by some router manufacturers – the fastest we’ve ever seen a router perform in our real-world tests is about 175Mbits/sec.
To get the maximum speed and range from your router, you may need to invest in range-extending equipment. An external or booster antenna for your router is rarely a wasted investment, especially if your router has been hidden away in a corner of the house by order of the style police.
You’ll need to check that your router model accepts external or replacement antennae – many of the free models handed out by ISPs don’t, which is another good reason to consider upgrading your router to one of the models on our A List.
Offices (or advanced home installers) might want to consider running a cable to a low-profile ceiling antenna. These are particularly useful in offices with false ceilings, and can provide a decent, omnidirectional boost for as little as £20 a go.
Alternatively, you could opt for a dedicated range extender/repeater device. You place the extender half-way between your current router and the laptop in the loft conversion that’s struggling to get a wireless signal, and you should receive an instant, no-fuss boost.
All the major router manufacturers offer range extenders for about £60, but although they all claim to work with each other’s equipment, conflicts with the various Wi-Fi chipsets usually mean it’s safest to buy an extender from the company that manufactures your router.
Powerline networking is another option for households where it’s simply impossible to eradicate the wireless interference, or when you can’t convince your neighbours that their leaky equipment is damaging your reception (as BT conceded when it had to buy a replacement TV for a homeowner whose leaky old box was wiping out the Wi-Fi for an entire street: “It’s very difficult to tell people they have a faulty television when they’re watching it.”)
You can even get the best of both worlds, with manufacturers such as D-Link and Netgear now offering dual HomePlug and 802.11n routers, so you can use the power lines to reach that back bedroom that’s out of Wi-Fi reach, and still use a laptop without having to jack an Ethernet cord into the wall.