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.
Call Handover and Coverage: All is not well... Conclusions
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  • Some1ne - Thursday, April 1, 2010 - link

    So let me get this straight. I'm supposed to pay AT&T for access to a device that uses my own Internet connection to patch up holes in their network? That's just ridiculous. It's AT&T's inadequate network coverage that makes these devices necessary in the first place, and now they're actually trying to profit off of having poor network coverage. Pretty much removes any incentive for them to improve their network, now doesn't it?

    These devices should be provided free of charge, as a "sorry you can't actually use the network that you paid to access" kind of token. Anyone who pays for one of these is just giving AT&T one more reason not to fix their coverage issues.
  • Alexstarfire - Thursday, April 1, 2010 - link

    I rather agree. Makes you wonder what they actually do with all the money they receive monthly. Also means that if you purchase one, much like how it should be if you use an unlocked phone, that your monthly bill should drop in price. Except in this case if they are using your broadband connection then it should practically be free since it provides next to no burden on them, though I don't know what happens after it goes through the connection.
  • therealnickdanger - Thursday, April 1, 2010 - link

    How do you know that the actual cost of the device and the technology driving it isn't already subsidized by your bill? Perhaps you're only paying 10% of what it really costs.
  • vol7ron - Thursday, April 1, 2010 - link

    Even if a subsidy were included, which would only cover some (not all) of the costs, the fact that people have to pay anything more for it is ridiculous given the nature of what a cell company is: a service. Cell phone companies are in business for one reason and by making you pay anything more to receive the core product is truely sad.

    There are other companies, like Cisco, that have built their own repeaters and Mobile-to-VOIP products, which I commend, because they are a technology company not providing the service. They're taking something bad, that they don't have control of, and making it bearable. Cell phone providers are at the other end, they have full control but are making you pay more, even though you aren't getting the initial benefit of what you're paying for in the first place.
  • zinfamous - Thursday, April 1, 2010 - link

    This is kind of where I sit with the argument. a one-time ~$150 cost to the customer *may* be cheaper in the end, than having a network-wide upgrade that increases costs across all customers, paying more and more per month.

    Perhaps it also improves access to those willing, and needing increased network performance, paying a bit more for the premium, while those customers with little need for the bandwidth go on about their normal use, paying what they always have. It's like...a single-payer network structure! :D
  • DoeBoy - Thursday, April 1, 2010 - link

    IT seems to me some people forget that companies are in business to make money. This is a great way for ATT to make a lot of extra money. I live in a rural area and i complain all the time in an area they say has coverage that does not at all. While this would aid me in getting better service it also would require me to pay for an inet connection which is not covered by att. Clearly they aren't a moral company when your service is so bad you have to have a product that uses some other technology(a la internet) and then charge the person not only for that product that gets you service but not even lower your bill since you technically arent using their towers really at all under this sucker. Clearly Verizon and ATT are both big 500lb gorillas. In europe its much easier to get a cheap cell phone deal and coverage. Clark Howard seems to think ATT and Verizon are going to end up being more corporate and smaller companies like t-mobile, cricket, metropcs and what not will fill in the void for the regular consumer.
  • Some1ne - Thursday, April 1, 2010 - link

    The problem is that when you look at the pricing matrix, not only is there a fixed upfront cost, there are also recurring monthly fees. It doesn't matter how much the up front cost is subsidized. The monthly fees mean that sooner or later, AT&T will be turning a profit on these devices.

    And even worse, the fees are higher if you're not already using AT&T as your ISP and/or land-line provider. That makes the least sense out of anything, since if you have a different ISP, then by running the femtocell you are completely unburdening AT&T's network, and dumping all the work onto someone else. The get to sell your bandwidth to someone else, and charge you more while doing it.
  • taltamir - Thursday, April 1, 2010 - link

    in computers, the technology is made mostly of sand... it costs practically nothing.
    It is the technology you are paying for...

    However there is one major component here, AT&T themselves look at it as a "cost cutting method"... in other words it is intended to cost them LESS, aka, they are making MORE of a profit on you if you get one of those then without.

    The whole thing is absurd. You pay hundreds of dollars for a black box device with tamper protection and absolutely horrid performance (compared to wifi), then you pay a monthly fee for the privilege of using said device...

    they should just put wifi in every device and have wifi be free (but they usually charge a monthly fee for that privilege as well)
  • ant1pathy - Friday, April 2, 2010 - link

    You are, of course, welcome to change carriers. If you feel the service you are recieving is subpar and another carrier would be better for you, the termination fee is probably less than the cost of the box. If you're continuing to pay for a service that does not meet your needs and you can't really use, then you are the pefect consumer.
  • Wolfpup - Wednesday, April 21, 2010 - link

    I completely agree. It's absolutely nuts IMO.

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