Connect with us

Cell phone signal question

Discussion in 'Electronic Repair' started by WbSearch, Aug 10, 2004.

Scroll to continue with content
  1. WbSearch

    WbSearch Guest

    Not sure if this is the correct forum, so I'll apologise if not.

    I have a calling plan that covers the 5 great lakes states. Worked fine
    everywhere, including Minnesota the past 3 years. This summer, in Minn. I
    could not get service north of Duluth. What I found strange, is when I turned
    the phone on, after about a minute, I got near full signal indicated. Then
    about 5 - 7 seconds later, it indicated no service, very consistently. If I
    tried to make a call, it wouldn't. I tried 911 and it went thru fine, (of
    course I ended the call as soon as it rang prior to connection).

    The question I have is, it possible that I am being blocked from service at the
    cell tower? The reason I am suspicious is 1) ATT is moving away from TDMA,
    trying to get everyone on GSM, and 2) according to the representatives I spoke
    with, the plan I have is a money looser for ATT. They dropped it, so I wonder
    if I am being blocked due to agreements they have with the local provider in
    MN, which ATT probably looses money when I use their cells.

    Another question is that when my new phone (Nokia 6360) switches towers, i.e.
    from roam to extended area, my call is droped. My wifes phone which is an
    older model (Nokia 5165) doesn't do this in the same area. The rep. tells me
    the newer phones do that and the older phone was more robust. Sound
    suspicious, or am I being paranoid?

    Thanks in advance.
  2. Bob Shuman

    Bob Shuman Guest

    As you will likely see from my return email address, I work at a US
    telecommunications company that provides cellular phone infrastructure to
    your carrier (AT&T Wireless Services) as well as many other large global
    service providers. I can tell you that your phone losing service until it
    is powered down and then rebooted is likely a (known) service provider
    issue. I would suggest that you call their customer service number and open
    a trouble ticket to let them know exactly when and where this problem was
    experienced each and every time it occurs.

    As to the issue of being dropped when you hand off between cell sites, this
    is either an RF or network design/implementation issue (again owned by the
    cellular service provider) or indeed your newer model phone is indeed "less
    robust" (less receiver sensitivity or higher S/N requirement). I'm not
    familiar with the two Nokia models you referenced, but can tell you that I
    have also heard comments that some of the newer model "3G" "3G-ready""high
    speed data-ready" etc. phones don't provide as much receiver sensitivity as
    the older (much less complex) phones. So, in this regard, I do not think
    that the AT&T representative was trying to pull a fast one on you. The only
    way you could actually confirm this is to experiment with the two phones at
    exactly the same time and place to see how they both behave. (This is
    because the infrastructure equipment acts differently under different
    network load conditions and depending on RF interference which is also
    highly time dependent.

    Lastly, with regard to AT&T's previously announced conversion from the North
    American TDMA standard to the GSM global standard, this could well be
    negatively affecting your service since AT&T needs to share (actually
    divide) their licensed frequency spectrum into TDMA and GSM specific
    components. In high traffic cells this will likely result in calls being
    blocked since TDMA capacity has been reduced from previous levels. It also
    creates additional complexity of managing the subscriber base with
    additional hand off possibilities (to GSM) if the newer more complex phones
    support multiple access technologies.

    I'd suggest you contact AT&T and let them know you are not pleased with the
    service and see what they do for you. By the way, another change that will
    be affecting you is the Cingular Wireless purchase of AT&T Wireless if this
    is approved as planned. The good news here for you is that Cingular is
    following the exact same technological path as AT&T. They too were TDMA
    only and are also in the process of converting to GSM and experiencing
    pretty much the same growth pains as they implement the phased conversion..

  3. WbSearch

    WbSearch Guest


    Thank you very much for the information. One thing I may not have made clear
    is I don't loose signal in the area I described, I cannot get any to last more
    than 5 - 7 seconds. Why I'm suspicious is that the phone shows very good
    signal about after a minute after powering up, then goes to no signal and no
    service within 5 - 7 seconds. This repeats in that specific area everytime I
    power on.
  4. Bob Shuman

    Bob Shuman Guest

    Not sure I understand your response below.
    You can't get "any" what to last more than 5-7 seconds?

  5. WbSearch

    WbSearch Guest

    Sorry, I meant can't get the signal to last. The indicator shows about 3/4
    bars for 5 - 7 seconds, then goes to none and indicates No Service.
  6. jakdedert

    jakdedert Guest

    I've a similar problem (Cingular, Sony/Ericcson t-220 GSM phone).
    Sometimes, even though according to the S-graph I have plenty of signal, I
    cannot connect. I'm in a large metro area, so the infrastructure should be
    there. This happens at odd times, sometimes even in the middle of the night
    when there shouldn't be much traffic. When it does happen, my wife's
    identical phone on the same account is affected the same way.

    I either get an endless 'connecting' message on the screen with no audio, or
    the internal 'beep beep' sound that indicates a 'no network' condition. If
    I then put the phone into a manual network search, it comes up with
    nothing...all the while, I still have plenty of indicated signal.


  7. Bob Shuman

    Bob Shuman Guest

    As indicated previously, Cingular and AT&T Wireless are in the process of
    converting their US networks from NA TDMA to GSM. Since the two
    technologies are mutually exclusive and can't co-exist (even though they are
    both Time Division Multiple Access - TDMA-based) in the same frequency
    spectrum, this means they needed to carve out existing spectrum from the
    TDMA users so they can assign/reserve it for GSM users. Thus the phone
    itself could well be seeing a very strong beacon signal from a nearby cell
    tower, but there may be no unused TDMA channels available for you to utilize
    so you get a fast busy and are unable to send or receive calls.

    The real problem here is that even if they could split the available
    bandwidth for each type (TDMA and GSM) of user (which they can't since they
    are constantly adding new users and converting existing users to newer GSM
    phones and they need to stay ahead of this game), they now have a smaller
    pool of TDMA channels and statistical theory verifies that this is
    guaranteed to result in a higher percentage of blocked calls.

  8. Guest

  9. jakdedert

    jakdedert Guest

    That would make some sense (if you substitute GSM for TDMA in the above
    paragraphs. I have a GSM phone.). FWIW, the first time this happened--in
    the middle of the night--I pulled out my old TDMA phone and it 'did' connect
    with the network. Of course, I couldn't make a call, but I got a

    Still, I can't figure out why it would happen in the middle of the night and
    last for maintenance being done in non-peak hours?

  10. L.

    L. Guest

    I had a Cell Phone once from Verizon.... It sucked so bad, every time I seen
    Mr. Can you hear me now - I wanted to grab him through the TV and wring his
    neck. I could STILL show Mr. Can you hear me now - SEVERAL dead spots.
    Actually, that commercial makes them look bad, if you still have to keep
    asking "Can you hear me now?" It shows a lack of confidence in their
    coverage. The very next step he takes, the one they don't show would most
    likely BE a dead spot......... BUT then again, he's most likely not talking
    to anyone anyway.

  11. I had a Cell Phone once from Verizon.... It sucked so bad, every time I seen
    It also depends on the phone.

    Me and my sister both have Verizon phones.

    My sister has a fully loaded phone from LG Electronics (tri-mode CDMA for
    Verizon), complete with custom ringtones, digital camera, color high resolution
    LCD screen, and etc. I live in an area where the signal is weak. She makes a
    call inside the house and it won't go through.

    Now, my phone is a Motorola StarTAC, also a tri-mode CDMA. It doesn't have any
    fancy features and is really just a basic phone. But, it can place a call in
    the same place inside the house where my sister's phone can't. This is because
    my StarTAC transceiver works at the highest legal power level while my sister's
    LG phone doesn't.

    People may laugh at the fact that I use a phone that isn't "stylish," doesn't
    have all the latest features, or looks very "old-school."

    But then I start looking cool when my phone works in places my friend's phones

    I wouldn't mind fancy features, but ultimately I want and need a phone that
    does its basic function well above all else. If you have to make a call, it's
    more important to have a basic phone that can do it in places where coverage
    isn't so great than have a stylish and loaded phone that can't under the same

    This is why I'll keep my StarTAC over any other phone until it breaks or until
    Verizon scraps their nationwide CDMA network.

    BTW, Verizon isn't nearly as bad as Sprint PCS. - Reinhart
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day