AT&T 3G MicroCell: A Comprehensive Exploration
by Brian Klug on April 1, 2010 1:55 AM EST- Posted in
- Smartphones
- AT&T
- Microcell Review
- Mobile
Femtocell handovers don't quite work..
So back to the AT&T MicroCell - handovers just didn't work for me. I didn't keep perfect track, partly out of frustration, partly because doing all this walking in and out and in and out of the house was physically exhausting, but to say 20% of calls handed over would be optimistic.
For this test, I called the local Automated Surface Observing System (ASOS) lines for several airports and simply walked a common path outside. The ASOS stations are for pilots to get the current weather conditions at airports quickly, but I use them as simple repeatable test calls. They terminate automatically after a few minutes to prevent misuse.
The most common mode of failure I saw was what's in the following video. The call starts fine, continues until the edge of microcell coverage, noticeably breaks up, and simply drops. All four of the iPhones I tested behaved the same way. Please forgive how shaky these are, it's challenging to walk rapidly, hold one phone, and take video with the other.
Of course, there were a few times where the handover went successfully. In these two videos, I unfortunately left WiFi enabled, but the handovers are hard and vertical and you can see "3G" disappear right after the transition. Listen carefully for how noticeable the audio change is; the phone has switched from UMTS to GSM to continue the call. Virtually all of the successful handovers at both location 1 and 2 were of this variety. After the call completed, I was clearly on 2G EDGE for some time.
But the most disturbing mode of failure happened on my daily device. During the vertical handover, there's loud audio corruption and distortion. Most of the time the call would then fail, a few times it successfully handed over.
This is something you should never, ever see on a modern cellular network. In fact, I was so shocked that I had my SIM replaced, rebooted multiple times, and did everything I could think of. Audio corruption still sporadically happened at locations 1 and 2, inexplicably. It's reasonably rare, but very alarming.
Call handover just doesn't work well. Even in location 1, where I could move freely about without dropping calls, migration from the MicroCell to the public 3G network would fail. That was an important test, because there are ample macrocells for the call to be migrated to; something just doesn't happen.
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nimck - Thursday, October 18, 2012 - link
Does anyone know how to configure the Microcell so that it's in a 'Disabled Mode' during certain hours of the day?? I'd like to lessen the radiation emission.lorace - Thursday, June 19, 2014 - link
We got the Microcell from AT&T because of poor signal strength. After it started working we were pleasantly surprised to see that our service bars had increased substantially. Now a new problem. We can't get our phones to transmit or received any picture messages. Anyone have an idea how to solve this problem? We called AT&T tech and they were clueless. lorace1@yahoo.comc21cg - Sunday, February 7, 2016 - link
i have had TWO of these crappy things, been on the phone for 17 months continously with att to get sorry help, have all the light lit up on the cell and NO service... so now what - oh and I even had to upgrade my wifi to satisfy att- hate ATT