Extending the Range of Wi-Fi

An 802.11n access point connecting to earlier-generation Wi-Fi devices will get some benefit from this "beam steering" capability in the new technology, Sharony says, but you only get the full benefits when 11n client devices are connecting to an 11n AP.

If you discover dead spots in a small Wi-Fi network, even when using 11n gear, you may be able to eliminate them simply by moving the single router or AP to a more central position, or moving it away from interfering obstacles, or up higher.

The difficulty often is extending Ethernet connectivity to the new location. If it can’t be done, the next simplest solution is a range extender.

Some SOHO network vendors sell simple wireless range extenders or repeaters that you position between the router and the coverage hole. They receive signals from the router and retransmit them at a higher power level into the dead spot.

Most only work with selected routers and APs from the same vendor. However, Netgear says its Universal WiFi Range Extender WN2000RPT (about $75) will work with any AP. Linksys also has a range extender/bridge product, the RE1000 ($79), coming soon.

These are all Band-Aid solutions, though. The best practice, Sharony says, is to conduct a site survey to identify potential dead spots and design a network that eliminates them from the get-go.

This is one of the important functions that wireless consultants like Sharony can perform. Network vendors and integrators can also do it for you.

One key when designing Wi-Fi networks, Sharony says, is to always build in a “cushion” of radio signal strength, a kind of margin of error, so that when multipath interference causes a dip in strength, as it inevitably will, the signal will remain strong enough to provide adequate connectivity everywhere in the facility.