Walt Mossberg

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Cell Towers For the Home Work Best in Worst Sites

If you have lousy cellphone reception in your house, you may have wished you had a cellular tower nearby. Well, now you can buy your own and plant it right inside your home.

Verizon (VZ), Sprint (S) and AT&T (T) all have started selling gadgets that act as mini-cell towers, broadcasting wireless phone service just like a real cell tower does, though over a much smaller area: a single house.

I’ve been testing one of these devices, AT&T’s $150 MicroCell, in two very different homes—my own house in the suburbs of Washington, D.C., and my son’s basement apartment in New York City. I chose AT&T for my tests because its network typically attracts the loudest complaints about bad coverage and dropped calls.

My verdict is that the AT&T MicroCell can, indeed, dramatically improve cellular reception and reliability, but it’s not a silver bullet. I found it works best in truly dire coverage locations, with little or no service, like my son’s apartment.

It is less useful in places like my house where the carrier’s outside towers provide some reception, even if you find that outside reception unreliable. I also ran into limitations on where you can place the MicroCell and how much of a home it can cover.

An AT&T spokesman insisted that the MicroCell is meant only for “a very small subset of customers with no or very poor coverage,” even though its Web site, at http://bit.ly/njH2s, includes videos touting the product for use in game rooms and home offices in any house. AT&T says it plans to tone down the Web pitch.

These devices, technically called femtocells, work like small versions of a cell tower. You plug them into your home broadband network, through which they acquire a signal from the carrier’s network. Then, they wirelessly redistribute that signal inside the home. Your cellphone treats this signal as if it came from a real outside tower, and latches onto it. But the signal supposedly is stronger and better, because it’s much closer and more focused.

While some people will welcome these devices as a godsend, others will resent the idea that they have to spend anything extra to get cellphone service they are already paying for.

Plus, when you make calls while your phone is connected to the MicroCell, you are still using up the minutes in your AT&T plan, just as you would on a regular outside tower, unless you buy an optional extra-cost MicroCell service plan. The company defends this by noting that you are still using its network, even though you are connected to it differently.

However, at least two of the carriers—AT&T and Sprint—are quietly giving away these devices to selected customers with terrible coverage whose patronage they presumably wish to keep. It is unclear to me how to qualify for these free devices, which appear to be handed out on a case-by-case basis.

The MicroCell, built for AT&T by Cisco (CSCO), is an 8.5-inch tall white, plastic gadget with an upside-down V-shaped base. As noted, it costs a one-time charge of $150, though AT&T will knock off $100 if you buy an optional $20-a-month plan that gives you unlimited voice minutes while using the MicroCell. It is only sold at AT&T stores.


AT&T’s device is 3G-capable, meaning it can also be used for data services at decent speeds, though the company recommends you rely on Wi-Fi for data. Verizon’s rival device, which isn’t 3G-capable, is called the Network Extender and sells for $149 after a $100 rebate, with no monthly fee. Verizon is working on a 3G model. Sprint’s version is called Airave. It costs $100, but requires a monthly plan ranging from $5 to $20. It also lacks 3G capability, though Sprint has just announced a 3G model that isn’t yet being offered for sale.


In both of my MicroCell test homes, the setup, which takes about an hour, went fine. You have to specify on a Web site which phone numbers can work with the MicroCell. Up to 10 phones can be listed, though the MicroCell can only handle four calls at any one time.

Range of 40 Feet

AT&T says the MicroCell has a range of 40 feet in any one direction, and can cover up to a 5,000-square-foot house. At my house, which is considerably smaller than that, it worked fine with both an iPhone and a BlackBerry, as long as I was in the same room as the little transmitter. In those spots, calls were made and received fine, and hardly ever dropped.

But it didn’t magically give me great coverage everywhere. First and foremost, because I do have fair AT&T coverage in most of my house, my two phones kept switching between the MicroCell and the outside AT&T tower when I wasn’t close to the device. When this happened, once in the midst of a conversation, the call cut off. Also, I could only plug in the MicroCell in the two locations where I had an Ethernet jack, neither of which happens to be in the two places in my house with the worst coverage. So, in those bad spots, the MicroCell signal was weak, and the outside tower kept taking over, even though it barely covers those two places.

AT&T says you can get around this problem by using a powerline adapter to create an Ethernet jack where you’d like one. These adapters route your Internet network through your electrical wires. But, in any case, the MicroCell mustn’t be located within a foot of your Wi-Fi base station and AT&T suggests it be within 3 feet of a window—further limitations on location.

In the Basement

At my son’s basement dwelling, where he barely got an AT&T signal on two generations of iPhones, things went much better, but only after some fiddling. His only standard Ethernet jack happens to be upstairs (it’s a two-level apartment). When the MicroCell was plugged in there, the signal was very weak in his basement abode directly below, constantly battling with the almost useless outside AT&T signal.

The problem was temporarily solved with a long, snaking Ethernet cable running down the stairs, but he viewed that an untenable solution. He finally plugged the Microcell into a basement jack on an Apple (AAPL) Airport Express gadget, which he uses as a Wi-Fi signal booster. While AT&T doesn’t officially support this approach, it worked, and the MicroCell has been a dramatic improvement for him.

Overall, I can only firmly recommend the MircoCell for situations where coverage is virtually nil, you are willing to spend an extra $150, and you can locate it in a way that works. If you just want to improve a spotty signal, or a few weak areas in your house, you might be disappointed.

Find all of Walt Mossberg’s columns and videos at the All Things Digital website, walt.allthingsd.com. Email him at mossberg@wsj.com.