Performance - Voice and SMS

Throughout the coverage radius, voice calls were basically as good as you'd expect them to be. Of course, right at the edge of the coverage radius there was noticable distortion and blocking like you'd normally expect. That said, calling works perfectly. I started with one device, and gradually added until I got to four devices.
 
Every device calling me - more calling in 2 minutes than I do in a month
 
There's really not too much to talk about quality wise, calling and SMS both work like they should when you're well within the range of the MicroCell. I did notice that call setup seemed to take longer occasionally, but don't have any explanation for it. There was also the occasional call that failed to setup, but again that was relatively rare. There wasn't any more perceptible audio lag than normal as well, something I've read callers definitely perceive occasionally. 
 
I realized this was a perfect opportunity to get some real numbers about how much bandwidth a phone call actually uses. To do so, I set myself back up machine-in-the-middle style, setup a network bridge, and watched traffic. I initiated a conference call with three phones to each other in conference mode, and made some noise.  This isn't as elegant as Anand's setup for call testing, but it gets the job done. I ran the test a few times with both one and two calls going, three just yielded the most smoothing. In practice, you'll see that bandwidth use is very uniform:
 
Three calls going
 
With a little math, we can really get a feel for how much bandwidth each call session is using:
 

This seems pretty reasonable, if a bit asymmetric. Then again, it's obvious that Cisco is being very careful about using limited upstream bandwidth, why not limit the return path just as much? Bear in mind that the same kind of downstream/upstream asymmetry applies across AT&T's 3G network, so these measures seem valid.

I also initiated call between two devices on the MicroCell and let it sit to see whether the call would drop after a long time - a number of people on the AT&T forums noted issues with longer calls. I successfully got up past a half hour, after which I terminated the call. I'm confident that it would have lasted should I have left it going. 
Performance Analysis: Multiple Devices Call Handover and Coverage: All is not well...
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  • A beautiful mind - Thursday, April 1, 2010 - link

    My Nokia N900 already uses the home/office wifi connection to access the internet, with the possibility to receive/make calls from/to skype.

    There is absolutely no extra functionality that is provided by the femtocell approach.
  • softdrinkviking - Thursday, April 1, 2010 - link

    For you and me, this is true.
    But not for everyone.

    That's the really sad thing about this device. It's designed as a way to nickel and dime poor souls whose homes are in a dead zone and absolutely have to answer their phone for business.

  • nafhan - Thursday, April 1, 2010 - link

    Great article, and you did an excellent job of diving into the tech behind the femtocell.

    An interesting follow up to this article might be to see what kind of results you get from purchasing an antenna and repeater. I've seen antenna/repeater setups online in the $350 and up range, and wondered how they would do. If they work OK, it might be a viable alternative, especially for people without good internet connections.
  • gwolfman - Thursday, April 1, 2010 - link

    Where is the print article feature on the new site?
  • Maroon - Thursday, April 1, 2010 - link

    They've been sneaking these things in Apple stores. No wonder the iPhone feelgood only lasts untill you get out of the store and have to rely on the "standard" AT&T network. LOL.

  • soccerharms - Thursday, April 1, 2010 - link

    Are you kiddin' me? I am going to approach this from two angles. The first being that this article is completely fake. ITS APRIL 1st people! The tech community should have an uproar for such a device. We buy internet and it is usually our responsibility to distribute it around the house with a router for wireless and whatnot. HOWEVER, we do not buy a wireless......phone plan with the intention on increasing a carriers crappy signal in our own house out of our pocket. That's ludacris! There is another much cheaper solution...........its called a LAN line with a cordless phone HA!

    The only company that could profit from a device like this would be Apple. But they would have to make it a little more shiney and put that quarter eaten logo on the side :)

    Let the battles begin....
  • Jaybus - Thursday, April 1, 2010 - link

    This is like buying an airline ticket only to find there is no flight. Since they don't have a flight, the airline offers to sell you your own airplane. You have to provide your own pilot, fuel, and maintenance, but you still have to pay them the full price for a ticket whenever you fly your own airplane. So my idea is to start a car rental business that has no cars. Anyone willing to pay AT&T for a microcell that uses their own Internet connection would surely be willing to pay me a rental fee for driving their own car.
  • HotFoot - Thursday, April 1, 2010 - link

    Eh... much of this market is iPhone users - people already willing to accept the concept of ecosystem lock-in. By a similar analogy to your car rental company, they're already willing to buy a car from a company that requires that they drive only on roads built or approved by that company, buy gas only at that company's stations, and buy car insurance from that company.

    Why not charge them for the roadside delivery of a jerry can of gas when the customer finds out the station filled their tank with water instead of fuel?
  • yacoub - Thursday, April 1, 2010 - link

    I give it a year or two before the first cancer danger report comes out. ;)
  • loydcase - Thursday, April 1, 2010 - link

    AT&T cell reception at my house is weak in spots. OTOH, if a femtocell allows me to rip out my landlines, it might be worth it. So I'd like to know if a femtocell would be viable for that purpose.

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