02-22-2012 10:28 AM
36 12
tools
  1. GNex Girl's Avatar
    My GNex constantly switches between 3G and 4G where I live and when I can get a 4G signal it is usually in the < -110 dBm range. According to VZW, I am either too close to the tower (and I am about 2 miles away) or the cells in my area have been sectorized to prevent me from getting good 4G in-building penetration. However, the problem happens outside in the neighborhood, too.

    Regardless of whether or not this is true, when my phone can detect any 4G signal at all no matter how low, it will try to grab it. During this switch from 3G to 4G, if I happen to be on a voice call, I drop the call. The same is true if my phone loses the 4G signal and switches back down to 3G - dropped call.

    I have called VZW about this and they say that makes no sense since the voice signal shouldn't be affected by the data handoff. IOTW - they don't believe me. Their "solution" for me is to set my phone to 3G only, which of course is not a solution for someone who wants to use 4G.

    Last night when I was on a call I decided to see what would happen if I changed the settings of my phone from having the preferred network mode be LTE/CDMA to CDMA during a voice call. I did and the voice call was promptly dropped. I then tried again during a voice call to switch the preferred network from CDMA to LTE/CDMA and again the call was dropped. So clearly something about this handoff drops voice calls.

    I was hoping some of you would try this yourselves with your phones and post here what happens when you do. Also if you could pay attention when you are on voice calls in areas where you have weak 4G coverage to see if the handoff from 4G to 3G or vice versa causes you to drop your voice calls and then post here with your results that would be much appreciated.

    Thank you!
    02-05-2012 11:36 AM
  2. GNex Girl's Avatar
    Also, if someone could tell me, since the 3G signal and the 4G signal are different frequencies, are there 2 different radios in my GNex - one for the 3G network and one for the LTE network? And what about voice calls? Are those on a different frequency, too?

    What is happening when I change the preferred network mode from LTE/CDMA to CDMA? Am I switching between radios in my device?

    Should I try to contact Samsung directly because I don't think VZW understands what is going on with my device?
    02-05-2012 11:44 AM
  3. Poseign's Avatar
    Also, if someone could tell me, since the 3G signal and the 4G signal are different frequencies, are there 2 different radios in my GNex - one for the 3G network and one for the LTE network? And what about voice calls? Are those on a different frequency, too?

    What is happening when I change the preferred network mode from LTE/CDMA to CDMA? Am I switching between radios in my device?

    Should I try to contact Samsung directly because I don't think VZW understands what is going on with my device?

    Yes, there are two different radios in this phone, one for CDMA one for LTE.

    From my understanding, 3G CDMA takes care of both voice and data, as does 4G LTE (Correct me if im wrong). When the phone switches between 3g and 4g, you are essentially switching which radio is taking care of your voice AS WELL as your data. Now with most phones this might not be a big problem, which is why Verizon reps may not "believe" you, but because of the galaxy nexus taking longer than usual to do this process, it could be dropping the calls while its trying to switch?

    This is all speculation to me. I have never dropped a call but i am also always set in CDMA only mode. All posts I have read about people dropping consistently dropping calls have been by people in 4g areas, so I'm just logically putting 2+2 together here.
    02-05-2012 12:40 PM
  4. GNex Girl's Avatar
    From my understanding, 3G CDMA takes care of both voice and data, as does 4G LTE (Correct me if im wrong).
    I am not saying you are wrong because I don't know the answer for sure, but from talking to the VZW reps (who many not know what they are talking about) I was under the impression that voice does not go over the 4G LTE network yet. Someday it will as VoLTE (voice over IP over the LTE network).
    02-05-2012 12:46 PM
  5. Poseign's Avatar
    I am not saying you are wrong because I don't know the answer for sure, but from talking to the VZW reps (who many not know what they are talking about) I was under the impression that voice does not go over the 4G LTE network yet. Someday it will as VoLTE (voice over IP over the LTE network).
    You could be right, I don't know for sure either. It just strikes me funny that the phone would drop a call then while trying to switch between the two modes.
    pauldroidr2d2 likes this.
    02-05-2012 12:48 PM
  6. GNex Girl's Avatar
    You could be right, I don't know for sure either. It just strikes me funny that the phone would drop a call then while trying to switch between the two modes.
    Same here and that leads me to believe that the problem then is with the design of the phone and this is why so many of us are having problems if we live in areas that get a 4G signal but the quality of the 4G signal varies.

    I am guessing that what happens is that when the phone goes to switch data radios, it briefly turns off the radio that is handling the voice call. I need to better understand the configuration of the radios in the device.
    02-05-2012 12:57 PM
  7. GNex Girl's Avatar
    Last night when I was on a call I decided to see what would happen if I changed the settings of my phone from having the preferred network mode be LTE/CDMA to CDMA during a voice call. I did and the voice call was promptly dropped. I then tried again during a voice call to switch the preferred network from CDMA to LTE/CDMA and again the call was dropped. So clearly something about this handoff drops voice calls.

    I was hoping some of you would try this yourselves with your phones and post here what happens when you do.
    Can anyone try this for me and tell me if it happens to them please - while on a voice call go into settings and switch the preferred network mode from LTE/CDMA to CDMA and then on another voice call do it from CDMA to LTE/CDMA? It is Sunday so it won't eat into your anytime minutes. Please!
    02-05-2012 03:17 PM
  8. umpirerob's Avatar
    Verizon's LTE is currently for data only. Verizon's 3G does one or the other, but not both at the same time. CDMA tech uses EVDO for data and the two don't allow both days and voice to work simultaneously. This was always a big thing for GSM carriers (at&t and T-Mo) because their tech did allow simultaneous usage. You should get both of your data is going over LTE because you'll be employing both the LTE and CDMA radios.

    Sent from my Thunderbolt
    GNex Girl and jroc like this.
    02-05-2012 03:39 PM
  9. GNex Girl's Avatar
    Verizon's LTE is currently for data only. Verizon's 3G does one or the other, but not both at the same time. CDMA tech uses EVDO for data and the two don't allow both days and voice to work simultaneously. This was always a big thing for GSM carriers (at&t and T-Mo) because their tech did allow simultaneous usage. You should get both of your data is going over LTE because you'll be employing both the LTE and CDMA radios.
    Thanks. A voice call should not be dropped if I lose the 4G LTE signal and drop down to 3G, right? If I were surfing the net as I was talking on a call and I lost 4G LTE, then I would lose my ability to surf the net, not drop my voice call, right?
    02-05-2012 04:00 PM
  10. jroc's Avatar
    Thanks. A voice call should not be dropped if I lose the 4G LTE signal and drop down to 3G, right? If I were surfing the net as I was talking on a call and I lost 4G LTE, then I would lose my ability to surf the net, not drop my voice call, right?
    All things being equal that's what should happen.
    02-05-2012 05:00 PM
  11. rfeagan's Avatar
    I changed the same setting, from LTE/CDMA to CDMA only, while on a call, AND while on my home wifi network.... the call still drops. I'm guessing it temporarily shuts down the cdma radio or something when you swithc the setting. Bummer.
    GNex Girl likes this.
    02-06-2012 09:02 AM
  12. GNex Girl's Avatar
    I changed the same setting, from LTE/CDMA to CDMA only, while on a call, AND while on my home wifi network.... the call still drops. I'm guessing it temporarily shuts down the cdma radio or something when you swithc the setting. Bummer.
    Thank you! I think the switch between LTE/CDMA and CDMA in either direction cuts off signal reception/transmission for a sufficient time to drop a call. It happens if I happen to be on a voice call and I lose 4G and the phone drops down to 3G.
    02-06-2012 09:58 AM
  13. willstilson's Avatar
    Verizon's LTE is currently for data only. Verizon's 3G does one or the other, but not both at the same time. CDMA tech uses EVDO for data and the two don't allow both days and voice to work simultaneously. This was always a big thing for GSM carriers (at&t and T-Mo) because their tech did allow simultaneous usage. You should get both of your data is going over LTE because you'll be employing both the LTE and CDMA radios.

    Sent from my Thunderbolt
    Except, of course, on the Thunderbolt and the Rezound. Those two phones are capable of simultaneous voice and data over 3G. Its a feature you never realize you need until you have it. Now I miss it since I have to keep my GNex in 3G mode.

    My Nexus also drops the call if i change the network.
    jroc likes this.
    02-06-2012 11:32 AM
  14. thebignewt's Avatar
    Thank you! I think the switch between LTE/CDMA and CDMA in either direction cuts off signal reception/transmission for a sufficient time to drop a call. It happens if I happen to be on a voice call and I lose 4G and the phone drops down to 3G.
    Good thread/observation. Clearly even though it "shouldn't happen" it does with this particular phone. Samsung might know why even if Vzn doesn't. I don't get 4G where I live, but I was in Phoenix over the weekend for the golf tournament and turned LTE on for the first time. Signal was about -110 to -120 for 4G and about -80-90 for 3G. I didn't have occasion to drop any calls. When I got 4G websites did download fast, but to me that's not worth dropping calls and draining the battery faster. I'll leave my LTE off for now even in Phoenix. It will be interesting to see whether Samsung can fix the handoff glitch. My guess is they can.
    GNex Girl likes this.
    02-06-2012 12:58 PM
  15. Poseign's Avatar
    Good thread/observation. Clearly even though it "shouldn't happen" it does with this particular phone. Samsung might know why even if Vzn doesn't. I don't get 4G where I live, but I was in Phoenix over the weekend for the golf tournament and turned LTE on for the first time. Signal was about -110 to -120 for 4G and about -80-90 for 3G. I didn't have occasion to drop any calls. When I got 4G websites did download fast, but to me that's not worth dropping calls and draining the battery faster. I'll leave my LTE off for now even in Phoenix. It will be interesting to see whether Samsung can fix the handoff glitch. My guess is they can.
    It is a very good observation, and it confirms what I personally have thought all along.

    Same here and that leads me to believe that the problem then is with the design of the phone and this is why so many of us are having problems if we live in areas that get a 4G signal but the quality of the 4G signal varies.
    I however do not believe it is the fault of the hardware, I believe its the fault of the software. Software is what tells these radios which should be on and which should be off, which means an update CAN fix this.
    02-06-2012 01:59 PM
  16. etbrandt's Avatar
    When you change the network mode it does reset the radios so dropping a voice call that way is expected behavior.

    I just did an experiment with organic handoffs, I have a room upstairs where I can catch a weak LTE signal. I was able to maintain a voice call in both a 4G-3G-4G and 3G-4G-3G (start to finish) manner, confirming data connectivity or lack with speedtest app.

    Only thing is I did this with 4.0.4 radios on GummyNex 0.66. I'll flash back to 4.0.2 radios and try again later.
    GNex Girl likes this.
    02-06-2012 05:39 PM
  17. GNex Girl's Avatar
    Only thing is I did this with 4.0.4 radios on GummyNex 0.66. I'll flash back to 4.0.2 radios and try again later.
    Thank you so much, that will be so helpful!
    02-06-2012 06:25 PM
  18. etbrandt's Avatar
    It still worked with 4.0.2 radios for me.
    GNex Girl likes this.
    02-07-2012 06:28 AM
  19. GNex Girl's Avatar
    It still worked with 4.0.2 radios for me.
    OK well that is good to know. Thanks again!
    02-07-2012 07:03 AM
  20. dmmarck's Avatar
    It is a very good observation, and it confirms what I personally have thought all along.



    I however do not believe it is the fault of the hardware, I believe its the fault of the software. Software is what tells these radios which should be on and which should be off, which means an update CAN fix this.
    Exactly. It's a software issue, or at least the majority of it.

    When you change the network mode it does reset the radios so dropping a voice call that way is expected behavior.

    I just did an experiment with organic handoffs, I have a room upstairs where I can catch a weak LTE signal. I was able to maintain a voice call in both a 4G-3G-4G and 3G-4G-3G (start to finish) manner, confirming data connectivity or lack with speedtest app.

    Only thing is I did this with 4.0.4 radios on GummyNex 0.66. I'll flash back to 4.0.2 radios and try again later.
    I've had similar experiences. In my room there is literally no 4G whatsoever (until the .4 radios), and I've successfully maintained a call (as of 30 minutes ago) when it went 4G, 3G, then 4G all in a matter of ~30-45 seconds or so.
    02-07-2012 09:28 AM
  21. xratede's Avatar
    im having the same problems somewhat. when i switch my phone to LTE/CDMA i have a great 4g signal but when i make a call, about 5 mins into the call, it drops and 4g disappears along with signal bars. if i set the phone to CDMA only I can make calls and receive data(not at the same time of course). Gonna take my phone to VZW in the AM because I may as well have gotten an iphone 4s if I wanted 3G only
    GNex Girl likes this.
    02-14-2012 03:28 AM
  22. TUCRACEMAN's Avatar
    This has been happening to me too. I can tell you that mine will drop the call if I toggle off 4g. Past few calls I've made in the house I've used the phone connected to my computer running logcat.
    ~D
    GNex Girl likes this.
    02-14-2012 10:58 PM
  23. JoeNM84's Avatar
    Will the new radios fix this then? Since in the 4.0.4 radios the switch between 3G and 4G is supposedly faster based on posts I've read from those with 4.0.4. So this issue really might just be a side effect of the long switch time the phone has that should be fixed in a future OTA update if it ever does come... for us stock users.
    02-14-2012 11:08 PM
  24. TUCRACEMAN's Avatar
    I'm using the 4.0.4 radios and i'm dropping calls randomly when it decides it wants to switch to 3g. So no, it does not fix the problem.
    ~D
    GNex Girl likes this.
    02-15-2012 04:05 AM
  25. xratede's Avatar
    My GNex constantly switches between 3G and 4G where I live and when I can get a 4G signal it is usually in the < -110 dBm range. According to VZW, I am either too close to the tower (and I am about 2 miles away) or the cells in my area have been sectorized to prevent me from getting good 4G in-building penetration. However, the problem happens outside in the neighborhood, too.

    Regardless of whether or not this is true, when my phone can detect any 4G signal at all no matter how low, it will try to grab it. During this switch from 3G to 4G, if I happen to be on a voice call, I drop the call. The same is true if my phone loses the 4G signal and switches back down to 3G - dropped call.

    I have called VZW about this and they say that makes no sense since the voice signal shouldn't be affected by the data handoff. IOTW - they don't believe me. Their "solution" for me is to set my phone to 3G only, which of course is not a solution for someone who wants to use 4G.

    Last night when I was on a call I decided to see what would happen if I changed the settings of my phone from having the preferred network mode be LTE/CDMA to CDMA during a voice call. I did and the voice call was promptly dropped. I then tried again during a voice call to switch the preferred network from CDMA to LTE/CDMA and again the call was dropped. So clearly something about this handoff drops voice calls.

    I was hoping some of you would try this yourselves with your phones and post here what happens when you do. Also if you could pay attention when you are on voice calls in areas where you have weak 4G coverage to see if the handoff from 4G to 3G or vice versa causes you to drop your voice calls and then post here with your results that would be much appreciated.

    Thank you!
    I'm gonna try this

    Sent from my Galaxy Nexus using Tapatalk
    GNex Girl likes this.
    02-21-2012 02:00 AM
36 12
LINK TO POST COPIED TO CLIPBOARD