Unlike AT&T's 3G MicroCell, which creates a cellular 3G hotspot by piggybacking on users' local Internet access, the WiEx zBoost cellular booster relays an existing signal from an external antenna to a repeater box installed inside.
That means the zBoost simply won't work if there's no usable signal outside. However, many users experience problems with spotty indoor service because their home or office building simply blocks enough of the available signal to make indoor calls unreliable.
For these types of users, the zBoost is ideal; they won't have to wait for AT&T to expand its 3G MicroCell test markets or to benefit from network upgrades that are slowly improving the mobile provider's service network.
Because the zBoost simply relays and amplifies a given band of mobile frequencies, it works with nearly any service provider. The XY-510 model works on both 800 and 1700 MHz bands, which supports all AT&T, Sprint, T-Mobile, and Verizon users, except for Sprint's Nextel subscribers using Motorola's iDen "push to talk" type mobile phones.
AT&T users can amplify both 2G/EDGE and 3G service that is available in their area using the device, enabling them to use the system to work around natural signal barriers related to elevation and topography or trees, walls and metal barriers. Of course, if there is no usable service in the area, the signal booster can't do anything about it.
In the box
For $400 or around $300 street, the xBoost XY-510 package includes an outdoor antenna (it looks like a baton) with a simple mounting kit, a 50 foot length of RG6 coaxial cable, and an indoor base station repeater, which requires a connection to a power outlet.
The outdoor antenna can be located anywhere there's a usable cellular signal, which might simply be indoors next to a window. For best results, WiEx suggests placement as high as practical, either inside an attic or, ideally, outdoors attached to the roof. Once cabled up the the indoor unit, the system can be powered on and hopefully will just begin working. There's no additional setup or configuration.
Status lights on the device indicate whether the external antenna is correctly connected and positioned. Too much signal or interference between the indoor and outdoor antennas can cause problems that will prevent it from working. For best results, WiEx suggests an outside antenna placement at least 15 feet above the level of the repeater box.
The inside repeater also has a jointed antenna that can be adjusted to account for different types of external antenna placement (such as whether both are set in the same horizontal plane or are installed on different floors).
After some experimentation, we found that the XY-510 was able to turn a completely dead zone inside our San Francisco flat into a functional area that supported not just phone calls and texts, but even pretty decent 3G data service. The difference between the signal available on the roof and that found outside on the sidewalk was also significant. Indoor signal is now better than I expect it to be when outside in my neighborhood.
The indoor antenna is omnidirectional, so it's best to place it as closest to the center of your home as possible. It is designed to provide 2500 square feet of coverage, although walls and particularly any sort of metal barriers will factor into how well the signal covers your living space.
WiEx warns that the device won't necessarily result in "more bars" on your cell phone display, as mobile phone indicators are both notoriously imprecise and only register major changes in signal; each bar typically represents 10db of signal strength (an order of magnitude).
Before hooking the device up, I could commonly "get" 3 to 4 bars of signal, even though I was not actually able to place a call, reliably send a text, or even have my phone ring for an incoming call. With the device in place, the level of service now seems quite reasonable, although there do see to be variations in usability related to weather or the time of day, which of course has a lot more to do with ambient levels of service rather than the performance of the zBoost system.
After some additional testing of the zBoost system, I'll report more on how well it works at my location, but early signs point to a major change in usability that could make the unit worth the expense to many people struggling with either spotty service or problematic locations such as working within a metal building or underground.
WiEx details its product offerings on the web at http://www.wi-ex.com/index.aspx
It's available on Amazon: Wi-Ex Zboost XY-510