AT&T 3G MicroCell

Do you frequently experience dropped calls or sluggish data service on an AT&T cell phone in a home (or small office) that’s supposed to be within the network’s area of coverage? AT&T’s 3G MicroCell might improve your wireless connection, although in my tests it wasn’t 100 percent reliable. And how much hassle is involved, or how little, depends largely on the layout of your home and home network.

iPhone reception in my downtown San Francisco loft has never been satisfactory, especially from the bedroom at the rear of the unit, some 40 feet from the windows. The vast majority of my calls have dropped within a minute or two. So I was eager to see if the MicroCell could help.

A white and orange-trimmed box about the size of a Nintendo Wii, the 3G MicroCell is a femtocell—it functions as a mini cell site that connects back to the mobile network via voice-over-IP through your wired broadband service.

AT&T is rolling out the $150 3G MicroCell in various markets; you can purchase the devices only in an AT&T store, although a phone representative can help you find a local outlet that sells them (or you could look up local availability on the AT&T 3G MicroCell website).

Because the FCC has mandated that femtocells must function only within a carrier’s area of coverage, the sales rep at an AT&T store in downtown San Francisco required that I state where I planned to operate the 3G MicroCell, and the instructions inside the box repeatedly advised me to notify AT&T should I move the device.

The carrier would be able to tell if I moved it, because, like other femtocells, the 3G MicroCell has a built-in GPS receiver that reports to the network once activated. A benefit of having the MicroCell tied to a specific location is that it enables E911 emergency service: If you dial 911 on your cell phone when it’s connecting via the MicroCell, emergency responders will know where you are.

The sales rep also offered to sell me an optional $20-per-month service that would allow me to make unlimited calls (domestically) when using the MicroCell, an option that might appeal to people who are considering dropping landline service completely. People who buy the plan also get a $100 mail-in rebate towards the price of the MicroCell, and AT&T also offers a $50 rebate if you buy a new DSL line along with the MicroCell.

Setup, from unboxing to first call, takes a couple of hours, mainly to let information about my MicroCell disseminate throughout AT&T’s system so that calls to my number are routed to the MicroCell when it detects that my phone is in range.

Before connecting a single cable, you must associate the specific unit you bought with your AT&T Wireless account by logging on to the carrier’s website and typing in the serial number located under the unit. During this process, you can also opt to have the MicroCell work only with other AT&T mobile phone numbers you specify (up to ten, including those on your account). Alternatively, you can leave the MicroCell in so-called unmanaged mode, so that any AT&T cell phone can connect to it as if it were a regular cell site. Either way, the device can support only four simultaneous users.

After completing online registration, you connect the MicroCell to your home network by running the included ethernet cable between a port on the MicroCell and a free LAN port on your router. (If you don’t have a network, you plug the cable that previously went to the modem into a passthrough port on the MicroCell, and then run the provided cable directly from the MicroCell to the modem.)

The setup guide gives very specific instructions on what to do next: Power down your modem and router, then power them up in that order, after which you plug the MicroCell’s AC adapter into a wall outlet.

None of this is difficult, but what can make it tricky is that you must place the MicroCell close to a window so that its GPS receiver can work. If your router and wall outlets are both reasonably close to a window, this isn’t a problem.

The provided ethernet cable is about 12 feet long; in my loft, this was just barely long enough to let me put the MicroCell about three feet from the window, the maximum recommended distance. (You can, of course, replace the supplied ethernet cable with a longer one.) However, I had no power outlet close enough to hook up the AC charger (which measures a little less than 5.5 feet), so I had to buy a 12-foot extension cord.

If you can’t place the MicroCell close enough to a window to get a GPS signal, the device has an external GPS antenna port, but you must buy the antenna yourself. AT&T neither sells nor supports external antennas, but I found standard ones (the type you might use with a portable GPS in a car) for about $20.

Within a few minutes after I plugged it in, indicator lights on my unit showed that both the network and the GPS connections were operating. And about an hour later, I received an e-mail and a text message on my iPhone confirming that my MicroCell had been activated.

On my iPhone, I could see that the MicroCell was providing coverage: The network name now read AT&T M-cell (instead of simply AT&T). And even in the farthest interior reaches of my loft, which formerly had about a couple of bars of coverage at best, I now saw five bars.

On the first couple of days after I installed the MicroCell, the service was pretty good. Calls stopped dropping, although voice quality didn’t particularly improve. I also noticed very slight pauses before my callers’ responses, the type I’ve heard in other VoIP services, but it was nothing I couldn’t live with. Data also was zippy, as fast as it’s ever been over AT&T’s 3G network.

But on the third day, things initially didn’t go so well. All of a sudden, my iPhone was dropping calls from locations fairly close to the MicroCell. Rebooting the MicroCell by disconnecting the power cord and waiting a minute or so before reconnecting seemed to address the problem.

However, my additional tests of the phone’s promised ability to hand off calls to AT&T’s conventional network were disappointing, though hardly surprising. The regular network is supposed to pick up calls once the MicroCell coverage ends, but in my loft building, the MicroCell coverage terminated in a concrete-surrounded interior staircase where there’s never been any signal, so there was no conventional network to pick up the call, which disconnected. Note that call handoff is a one-way affair: Calls started on the conventional network do not move over to a MicroCell.

Macworld’s buying advice

Overall, the AT&T 3G MicroCell does appear capable of improving service in the home, but not without occasional glitches. (The manual says that like other tech gear, the MicroCell sometimes needs rebooting, so it seems AT&T must be aware of its imperfections.) I’m not completely thrilled with it, but on balance it seems to help my service more than it hurts.

[Yardena Arar is a contributing editor for PCWorld.]