The faster Wi-Fi you should know about

     

Beamforming technology, built into many 802.11ac routers, focuses the signal for faster transmission. BY ERIC GEIER

BEAMFORMING IS ONE of those concepts that seem so simple that you wonder why no one thought of them before. Instead of broadcasting a signal to a wide area, hoping to reach your intended target, why not concentrate the signal and aim it directly at the target? Sometimes the simplest concepts are the most difficult to execute, especially at retail prices. Fortunately, beamforming is finally becoming a common feature in 802.11ac Wi-Fi routers, at least at the high end.

First, a bit of background: Beamforming was an optional feature of the older 802.11n wireless networking standard, but the IEEE (the international body that establishes these standards) didn’t spell out exactly how it was to be implemented. The router you bought might have employed one technique, but if the Wi-Fi adapter in your laptop used a different implementation, beamforming wouldn’t work.

Some vendors developed pre-paired 802.11n kits (with Netgear’s WNHDB3004 Wireless Home Theater Kit being one of the best examples), but such kits tended to be expensive, and they never had much effect on the market.

The IEEE didn’t make the same mistake with the 802.11ac standard that’s in today’s high-end devices. Companies building 802.11ac products don’t have to implement beamforming, but if they do, they must do so in a prescribed fashion. This policy ensures that every company’s products will work together.

If one device (such as the router) supports beamforming but the other (such as the Wi-Fi adapter in your laptop) doesn’t, they’ll still work together; they just won’t take advantage of the beamforming technology. Beamforming can help to improve wireless bandwidth utilization, and it can increase a wireless network’s range. Such enhancements can in turn improve video streaming, voice quality, and other bandwidth- and latency-sensitive transmissions.

Beamforming is made possible by transmitters and receivers that use MIMO (multiple-input, multiple-output) technology: Devices send and receive data using multiple antennas to increase throughput and range. MIMO was introduced with the 802.11n standard, and it remains an important feature of the 802.11ac standard.

How beamforming works
Wireless routers (or access points) and wireless adapters that don’t support beamforming broadcast data pretty much equally in all directions. Think of the wireless router as a lamp without a shade: The bulb (transmitter) radiates light (data) in all directions. Devices that support beamforming focus their signals toward each client, concentrating the data transmission so that more data reaches the targeted device instead of radiating out into the environment. Think of putting a shade on the lamp (the wireless router) to reduce the amount of light (data) that’s radiating in all directions. Now poke holes in the shade so that concentrated beams of light travel to defined locations (your Wi-Fi clients) in the room.

If the Wi-Fi client also supports beamforming, the router and client can exchange information about their respective locations in order to determine the optimal signal path. Any device that beamforms its signals is called a beamformer, and any device that receives beamformed signals is called a beamformee.

Netgear’s Beamforming+
As mentioned earlier, beamforming support is an optional element of the 802.11ac wireless networking standard, and any vendor offering the feature must adhere to a specific technique. But the vendor can also provide other types of beamforming in addition to that standard technique.

Netgear’s Beamforming+ (go.pcworld.com/beamplus) is a superset of the beamforming technique defined in the 802.11ac standard, so it’s interoperable with any other 802.11ac device that also supports beamforming. But Beamforming+ does not require the client device to support beamforming, so you could see range and throughput improvements by pairing one of Netgear’s routers—specifically, Netgear’s model R6300 (go.pcworld.com/r6300), R6200, or R6250—with any 5GHz Wi-Fi device. Netgear’s R7000 Nighthawk (go.pcworld.com/nighthawk) router also supports beamforming on its 2.4GHz network.

Of course, Netgear is not the only router manufacturer to support beamforming. The feature is becoming common on higher-end Wi-Fi routers and access points. If you’re in the market and you want a router that supports beamforming, check the specs on the box or at the vendor’s website. For three other router options, consider the Linksys EA6900, the D-Link DIR-868L, and the Trendnet TEW-812DRU.


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