Why your Wi-Fi speed sucks and how to deal with it

In some of our WiFi speed tests, it wasn't uncommon that a 802.11n connection with devices only a few meters apart (and with only wall in between) can fall back to a mere 2-15 Mbps. And here's where you run into problems:
· 0.5-2 Mbps: Is enough for all your basic chatting and mailing services, though it will slow down some content-heavy websites -- especially if you've got a 20+ Mbps downpipe.
· 4-5 Mbps: Enough for handling all websites and basic video streaming.
· 20+ Mbps: This is the minimum you need to even consider HD streaming. Even though, the typical bitrate of a 720p iTunes TV show is 2-6Mbps, your router needs to compensate for dropouts, other connected clients and prebuffering.
· 50+ Mbps: Enough for 1080p movies and over-the-air backups.
If you're sick of slow WiFi speed but hate to go back to Ethernet, we've got a handful of tips that'll help boost weak signals.

1. Check your router's eco settings
Some routers are set up with their "Power savings" mode on by default. The goal: save a few milliwatts. Unfortunately, this commendable approach reduced bandwidth disproportionately. Although my trusty Linksys WRT610N router wasn't set up with unnecessary power savings in mind, I turned on its low power modes just to see the effects:

If you value bandwidth over minimal power savings, check out the router's setting and look for entries called "Transmission Power" or various Eco modes. Turn them OFF. Also, do check if your router sports some sort of "Automatic" transmission setting. You may want to turn it off and go "100%" all the time.

2. Overcome the laws of physics
Unfortunately, the laws of physics sometimes stand in the way of proper wireless bandwidth and signal strength (where can I file a complaint?). First of all, the distance between your router and the wireless adapter is a more relevant factor than you might think. Here's a rule of thumb: Just by doubling the distance between router and client you can expect throughput to shrink to one-third of its original value. A wireless repeater, which will set you back $20-$100, should boost your signal noticeably.
In addition to distance, the other wireless signal killers are the objects and elements that are in the way of throughput, namely water and metal. Water acts as a blockade for 2.42GHz signals, so it may be wise to get all objects in your home or office that contain any form of liquids out of the way (this includes radiators and flower pots -- no kidding!). Also make sure that metal objects are not in the way of your router and your clients: this goes for metal furniture as well as metal boards, tech gear, etc.
Keep in mind that smooth and shiny surfaces are prone to reflecting signals and thus either creating drops or massive signal problems.

3. Upgrade your router's antenna
Packet loss and weak throughput is often caused by weak antenna design. Good news: You can replace the built-in antenna of your router with something much more powerful. It's a bit of a hassle, but it may make the difference between a slow connection (or none at all) and a speedy line to your router!
Depending on your setup, you'll want to go with either an omnidirectional antenna that scatters the signal throughout your home or a directional antenna if most of the devices that are in need for good throughput are in one room. Probably the best and most extensive guide for replacing antennas is Binary Wolf's.

4. Figure out the best spot for your router
Use a Wi-Fi heatmapping tool to measure the impact of distance, frequency changes and building structures on signal strength. Two tools that are great for this job are NetSpot for Mac and Heatmapper for Windows. Both tools allow you to track Wi-Fi coverage in your office or home. In this example, we're going to show you how NetSpot works: Once you've installed the software, type in a new "Site Survey" name and hit "Blank Map". You can also select a floor plan of your home or office and get an exact map. If you're more creative, I suggest you select the "Draw Map" feature and start drawing your own floor plan. Next, define the scale by determining the exact distance between two spots. Hit "Let's get started" and just walk around. Click the spot on the floor plan that you're currently standing in:

Obviously, the more points you scan, the more exact your Wi-Fi heatmap. Once you're done, you end up with a map that shows you not just the signal strength but also the throughput of your Wi-Fi network.

5. Varying CPU frequencies and their effect on wireless signals
Your computer's motherboard is also working in the "Gigahertz" spectrum. That "noise" is being picked up by your built-in Wi-Fi transmitter. Unfortunately, the higher that noise is, the more likely it is for your wireless adapter to lower bandwidth automatically (by lowering the link-rate and avoiding frequency interferences). As CPUs these days clock dynamically, the Wi-Fi adapter needs to constantly adapt the link rate which not only causes a variation in Mbps but may also be the cause for dropped connections. Especially on laptops, the Wi-Fi adapter is often built close to the memory and CPU bus, which is a major source for problems.

Of course, this all depends on the design of your Wi-Fi adapter, but if these symptoms sound familiar you might solve this issue by getting an external adapter. Some of these adapters, such as my Linksys adapter, even have a little stand that's connected via a long USB cable. Putting that kind of space between the Wi-Fi adapter and your CPUs noise is likely to help a lot. Of course, that's not too handy when you're traveling, but at home it's a viable option. Typical Wi-Fi adapters such as the Linksys AE2500 (802.11n dualband) or the MSI US310EX will set you back between $20 and $40 and they're worth every penny.