AT&T's Mini Home Cell Phone Tower
Apparently AT&T Microcell users are getting LOTS of dropped calls after installation of the AT&T Microcell / Femtocell after a proper installation. Does there need to be more disclosure about which cable and wireline network the Microcell works best with? Can Comcast, Cox, Time Warner, Cable Vision purposely sniff out AT&T Microcell packets and make the calls drop similar to Vonage and Skype? It also appears that there is a not so friendly competition between the Microcell and the macro cell tower outside for domination. If the macro cell tower strenght is too strong, the microcell hands off the call. Once that happens it cannot go back. If your call is in macro and the signal starts to degrade, you end up with a dropped call. Why does this happen? Well RF engineers tell us it's because the cell tower outdoors doesn't know the Microcell exists on the network and thus your the signal will not be optimized. Sometimes too many cell phone towers or Microcells in an area can cause dropped calls as well.
Here is are 3 examples of a users having problems:
San Francisco - All the lights are on and my iPhone reads AT&T M-CELL with 5 bars all over the house. I've got a 50MBit down/10MBit up connection which passes all the VoIP online tests with flying colors (very little jitter, 0.0 packet loss etc..) It's hooked to a reasonably new dual channel Cisco wireless router. The problem is that Calls are failing all the time - while the bars stay solid at 5. Occasionally, I'll go a day or two without a dropped call, but then I'll have 5 or 6 dropped calls in a row. I've had to disable 3G on the iPhone just to maintain a conference call for more than 10 minutes without dropping. I've restarted it a couple of times and that doesn't appear to do anything.
San Diego - I've had my MC for a couple of weeks now. Where I live in San Diego, it is very hilly. Macro cell coverage is very spotty. In the front of my house, I get absolutely no bar coverage. In fact it typically says "Searching for Network". In the back of my house approx 50' away I get 1-2 bar macro coverage. I have experimented with the location of the MC and here is what my very superficial testing has shown. It seems to be important to locate the MC in a location where you get the worst macro cell coverage. It somehow appears, that there is a not so friendly competition between the MicroCell and the cell tower for domination. If the macro cell strenght is too strong, the microcell hands off the call. Once that happens it cannot go back. If your call is in macro and the signal starts to degrade, you end up with a dropped call. So now with the MC located in the front of my house, I get 5 bar coverage and almost never drop a call throughout most of the house. However, if I start a call up front and start walking towards the rear, once the tower strength starts to exceed the MC strenth that appears to be the problem area. If it hands off to the cell tower I typically have no better than 50% chance of completing the call before it is dropped.
Salt Lake City - I just bought a MicroCell yesterday in Salt Lake City and had my first two calls dropped. So far, I'm less than impressed. Let me know if you or anyone has any suggestions. If not, this might be a short-lived purchase.
Is anyone else experiencing this kind of performance? Is there a firmware update of some kind?
Read more at the AT&T Wirless Forum
Call Failed or Dropped Calls?