02-08-2011 9:10 AM
So I had a microcell about a month ago and returned it after about a week.
The reason I returned it was due to the fact that I'd start a call on the MC and then about a minute into the call, it would switch to the cell network and due to bad signal would then drop the call.
I called support and eventually got a call back from an engineer that said that if there is ANY kind of cell signal available for a cell phone that the phone would take the cell signal over the microcell, no matter how strong that signal was. (I literally could start a call standing in front of the thing and my phone would switch to the cell network).
Has anyone else had this issue at all? I still have major signal issues which makes my phone basically useless to me unless I am not in my house and would consider picking up a new one if the above issue could somehow be mitagated.
02-08-2011 11:17 AM
I had a similiar problem when I first got my MicroCell about a year ago. Somewhere along the line something changed and I no longer have the issue. I rarely experience a dropped call when connected to the MC now, even if the competing macrocell signal is about the same strength as what I'm getting from the MC in a particular part of the house.
At&t is making changes to the system, either firmware/software updates to the MC, or changes to their backend, or both. One recent change is users in some parts of the country have seen their 3G upstream through the MC increased from an almost useless 56 kb/s to a more useful 200 kb/s.
Unfortunately, at&t is so close lipped about those changes that it's impossible to know if anything has changed in your area that may improve performance. I guess you could always try another MC if the store where you buy it will still give you 30 days to return it.
02-08-2011 11:28 AM
This is a common complaint. Just search this board for "dropped call". Your call will be handed off to the local tower, but won't be handed back to the microcell. It does not seem that the microcells are as integrated into the network as the macrocell towers are. With a macrocell, calls can be handed back and forth between towers without dropping. In my case, I can get a rudimentary Edge network signal of between one and two bars in different parts of my house. Upstairs is better than downstairs. As a result, I tend to get more dropped calls when upstairs. Even upstairs with a better macrocell signal, I've been able to hold a conversation for a few (<5) minutes before the call was dropped. It probably depends on how often my phone polls for a macrocell signal. All-in-all, it's very frustrating in that you begin to anticipate the call getting dropped.
02-09-2011 4:53 AM
What I can't understand is this sounds like a straight forward fix. Why can't AT&T just roll out a firmware change that gives priority to the stronger signal? Is there something I'm missing here?
02-09-2011 5:02 AM
It's probably not that simple.
When I'm wandering around my house on a call through the MicroCell there are times when I may be in an area where I still have MicroCell coverage but a macrocell has a stronger signal. I don't want the call to jump to the stronger signal because once it does, it won't transfer back.
That is the very problem I had early on. A call would jump to a macrocell and then eventually drop because I'd move out of macrocell coverage (which is why I have the MC in the first place). Now it seems like my MicroCell has priority. Once I'm on it I stay on it until I have no MicroCell signal.
As I said earlier in this thread, I don't know why the MicroCell seems to work better around here than it does in other areas and at&t isn't sharing any info that would help in understanding. But to me an improvement would be changing the protocol so the MicroCell/macrocell transfer is bi-directional. If you jump to a macrocell great...as long as you can then jump back to the MicroCell when you need it.
I'm not holding my breath.
02-09-2011 8:48 AM
My limited understanding of GSM, UMTS and the Microcells is that inward handoff is not possible given the current architecture. The local cell sites don't know that a microcell exists (after all, there might be dozens of them within its range), and microcells don't just accept any old phone that happens along. So the Macro network doesn't keep the Microcells in the 'neighbor list' that they share with each other. If a cell site hands off a call, it has to know where it's going to go next, and the option to hand off to other than a neighbor isn't conveniently wired in to the standard.
The microcells, by contrast, can hand out because they do have a neighbor list because of their geolocation, among other reasons.
02-09-2011 9:29 AM
I hear what you're saying, but it seems that some kind of controller in the background must have a neighbor list that includes macro and microcells. That controller/server is where you're phone number is registered to your MicroCell and should know when your phone is in range of a MicroCell where it's registered.
I don't see why if my call can be handed off from my MicroCell to a macrocell why it can't be handed back off in the other direction 30 seconds later.
But then we're guessing, aren't we?
02-09-2011 12:08 PM
The problem is that with the Microcell in the mix, the macrocell will potentially have to maintain a separate neighbor list for every phone it can see (imagine a worst-case scenario where all of them had a microcell sitting next to them and were able to also see the same macrocell site), which is probably asking too much.
I actually think it would make more sense from an architecture standpoint for the microcells to be permissive (that is, give priority to the owner's phone, but allow anyone within range to use the microcell). Then they might really be able to be equal partners in the mesh, even if their footprint was much smaller.
02-09-2011 12:17 PM
That would probably work for me since I have more-or-less unlimited bandwidth for a residential installation. I'm not so sure if someone had DSL with minimal pipeline if they'd want to be sharing it with anyone who walked by their location.