Breaking Band: Tri-band LTE / eCSFB issues thread

[moeSizlak]

Just obtained an HTC M8 (One) with tri-band LTE and I'm curious if I'll be impacted by any CSFB issues in Buffalo,NY.  Looking at the maps, the vast majority of all sites in my area are 3G accepted, with about 60-70% being 3G/4G accepted.  So I'm assuming that I should be OK.

 

One question:  When you're in an area with an LTE signal and operational CSFB, but you are on wifi, does the phone maintain a connection to EVDO/1x to listen for calls, or to the LTE?  (In other words, does being connected to wifi preclude you from LTE/CSFB-related issues with call receiving?)

 

Thanks.  This site rocks.

[Paynefanbro]

Just obtained an HTC M8 (One) with tri-band LTE and I'm curious if I'll be impacted by any CSFB issues in Buffalo,NY.  Looking at the maps, the vast majority of all sites in my area are 3G accepted, with about 60-70% being 3G/4G accepted.  So I'm assuming that I should be OK.

 

One question:  When you're in an area with an LTE signal and operational CSFB, but you are on wifi, does the phone maintain a connection to EVDO/1x to listen for calls, or to the LTE?  (In other words, does being connected to wifi preclude you from LTE/CSFB-related issues with call receiving?)

 

Thanks.  This site rocks.

It stays on LTE periodically checks for calls and texts.

[Paynefanbro]

CSFB doesn't effect texts as those are transmitted over LTE.

Texts and calls go over 1x.

[moeSizlak]

Texts and calls go over 1x.

No, you can send receive SMS/MMS over LTE, as the article states:

 

http://s4gru.com/index.php?/blog/1/entry-357-nexus-5-and-lg-g2-experience-temporary-sprint-lte-connectivity-issues-due-to-circuit-switched-fallback-technology/

 

 

EDIT:  Since the initial publishing of this article, it was discovered that Triband LTE devices were capable of sending/receiving texts via LTE.  It is only voice calls that require Triband LTE devices to shunt back to the CDMA network via CSFB.  The article has been edited to make this clarification.

[moeSizlak]

It stays on LTE periodically checks for calls and texts.

 

Well first of all, it does not "periodically check" for calls and texts.  That makes it sound like your device is polling for calls.  That would be ridiculously stupid.  Instead CSFB tells the device, via LTE, to switch itself to CDMA/1X to receive a call.  Texts are received over LTE without switching to CDMA/1X (To prove this just try sending or receiving SMS or MMS while on a call.  It works fine.)

[Paynefanbro]

Thanks for correcting me. But next time, try not to use "first of all". It comes off as hostility and is seen as rude. You're welcome for my, atleast partially right answer in that the device does stay on LTE while on Wi-Fi.

[travismheim]

Just obtained an HTC M8 (One) with tri-band LTE and I'm curious if I'll be impacted by any CSFB issues in Buffalo,NY.  Looking at the maps, the vast majority of all sites in my area are 3G accepted, with about 60-70% being 3G/4G accepted.  So I'm assuming that I should be OK.

 

One question:  When you're in an area with an LTE signal and operational CSFB, but you are on wifi, does the phone maintain a connection to EVDO/1x to listen for calls, or to the LTE?  (In other words, does being connected to wifi preclude you from LTE/CSFB-related issues with call receiving?)

 

Thanks.  This site rocks.

Just because sites are 3G accepted doesn't mean you wont have eCSFB issues. All of Syracuse is 3G or 3G/4G accepted and there are eCSFB issues all over the place here. Also, if you are on wifi and are connected to LTE on a tower that has eCSFB problems, you will have call problems. I don't see you having a problem with that on your HTC One, but I deal with it all the time on my N5 using the .15 base band which ignores eCSFB availability.

[burnout8488]

Texts are received over LTE without switching to CDMA/1X (To prove this just try sending or receiving SMS or MMS while on a call.  It works fine.)

 

 

This has always been possible on non-LTE devices as well. You can call and text over 1x simultaneously. Just can't use data. 

 

While in a call on an LTE device, you would be using 1x for voice, and 1x for any texting you might be doing. (iMessage excluded)

[S4GRU]

iPhones do not use CSFB, but actually do poll for calls every few seconds by undetectably switching off LTE for a fraction of a moment and checking the CDMA network. If it does discover one on the network coming for your line, it stays on CDMA and accepts the call. If nothing is there, it goes back to LTE. It happens so fast, that it is imperceptible to the user.

 

However, since the iPhone is single transmission path, this means CDMA voice users do lose data connectivity if they accept that voice call.

 

All other OEMs use CSFB to my knowledge. And CSFB does not require the device to poll the network. The network tells the device via CSFB to accept the call. Then the call rings through and LTE is disconnected.

 

Robert via Samsung Note 8.0 using Tapatalk Pro

 

 

[moeSizlak]

Interesting, thanks for the info.

 

Here's what I'm seeing with my HTC One M8 in Buffalo, NY:  I have a very strong LTE signal at both my home and my work, and most points in between.  All towers at home, work, and in between are at least 3G accepted.  Upon booting the phone, it will happily connect to LTE and stay connected.  If I drive for a while, to home or to work, it will switch to 3G and *never* switch back, ever.  Even if I drive back to where I started from (where I had a strong and consistent LTE connection).  

 

The only way the phone will EVER connect to LTE again is if I either reboot it, or toggle airplane mode on and off.

 

I am very frustrated and don't know if it is the phone, or an eCSFB issue, or what...

[transitwatch889]

Interesting, thanks for the info.

 

Here's what I'm seeing with my HTC One M8 in Buffalo, NY:  I have a very strong LTE signal at both my home and my work, and most points in between.  All towers at home, work, and in between are at least 3G accepted.  Upon booting the phone, it will happily connect to LTE and stay connected.  If I drive for a while, to home or to work, it will switch to 3G and *never* switch back, ever.  Even if I drive back to where I started from (where I had a strong and consistent LTE connection).  

 

The only way the phone will EVER connect to LTE again is if I either reboot it, or toggle airplane mode on and off.

 

I am very frustrated and don't know if it is the phone, or an eCSFB issue, or what...

it's an eCSFB issue as you stated. My tower by be would do the same on my ONE max from November2013 till like maybe 3 weeks ago I had consistent tower irregularities due to that. Nothing is wrong with the phone. Sprint will just get to it optimize it when they can... So put it in your head it won't be fixed to July and go about your business. In the mean time u will have have to toggle the connection to keep it on if u don't lose it or hand off while in the same area.

[jorge141020]

Shentel must have pushed out an update last night in my area.  I've had the HTC One M8 since Thursday and needed to keep it in CDMA only mode to make and receive calls due to, what I assume, was the lack of CSFB in my area.  This morning, I put my phone back into LTE/CMDA mode and had LTE for my entire drive into work from Inwood, WV to Hagerstown, MD along Interstate 81. Before, my phone wouldn't connect to LTE in this area even when it was in LTE only mode.

[moeSizlak]

Shentel must have pushed out an update last night in my area.  I've had the HTC One M8 since Thursday and needed to keep it in CDMA only mode to make and receive calls due to, what I assume, was the lack of CSFB in my area.  This morning, I put my phone back into LTE/CMDA mode and had LTE for my entire drive into work from Inwood, WV to Hagerstown, MD along Interstate 81. Before, my phone wouldn't connect to LTE in this area even when it was in LTE only mode.

 

How do you put it into LTE Only mode?  I do not see any such option.

[jorge141020]

How do you put it into LTE Only mode?  I do not see any such option.

Enter *#*#4636#*#* on the dialer.  Select Phone information from the menu that pops up, then scroll down and you'll see a 'Set preferred network type' option.  Tap the dropdown and select LTE Only.

[mhuling]

Hey guys I've been reading up on this like crazy since I got my M8, but I'm still unclear on one thing. I'm technically in the Nashville market, but in a city called Maryville, right outside of Knoxville. While using the GS4, Iphone 5/5S, M7, etc I was able to connect to LTE almost everywhere in town. Now that I have this M8 I can't get LTE anywhere. So I take it the CSFB hasn't been installed yet in my area. That much I am clear on. 

 

The part that I'm concerned about is this: The device is supposed to recognize that CSFB isn't installed, then kick back to 3G and stay there, correct? My problem is that my phone is going a step further and kicking back to 3G, but then losing THAT connection very frequently (if it ever truly makes a data connection at all) and incoming phone calls are arriving to me with about a 5% success rate. Texts are also spotty at best. So essentially right now I have a very nice wifi enabled device in my pocket.

 

I can't seem to find anywhere in the explanation of all this where 3G will be so greatly affected. This has me concerned that I actually have a bad device on my hands and need to get a replacement. 

 

Is there anyone that can definitively tell me that this is a side effect of CSFB and not a bad phone?

Edited April 3, 2014 by mhuling

[shifted]

Once cell sites have had their 3G vision stuff completed how long does it take for the CSFB to start working?  In Minneapolis a bunch of the towers look upgraded according to the completed maps but my Nexus 5 will not connect to them yet for LTE.  It will connect to towers like 30 miles south so I know my phone's LTE works fine.

[njjdnt]

Once cell sites have had their 3G vision stuff completed how long does it take for the CSFB to start working?  In Minneapolis a bunch of the towers look upgraded according to the completed maps but my Nexus 5 will not connect to them yet for LTE.  It will connect to towers like 30 miles south so I know my phone's LTE works fine.

There is no set time.  A couple towers in Roseville are going on over two weeks now. 

[flyloc2]

I just read where GPS won't work while on a call while using ecsfb.  Is that true?  That's a feature that I use a lot while on a call.

[JWMaloney]

I just read where GPS won't work while on a call while using ecsfb. Is that true? That's a feature that I use a lot while on a call.

GPS will work without a network connection. Downloading map tiles or navigation will not. If you cache map tiles by viewing an area and searching for "Ok Maps" and you begin the navigation before the call, you can continue to use it while on a call, provided you don't deviate from the route.

[flyloc2]

Oh Ok.  Sprint needs to come out and start giving out facts and not let the media dictate how Sprint's network will run.

[travismheim]

I just read where GPS won't work while on a call while using ecsfb. Is that true? That's a feature that I use a lot while on a call.

Depending what navigation you use, you can cache/download maps for offline use.

 

Sent from my Nexus 5 using Tapatalk

 

 

[bobloiy]

So I'm on an MVNO named UbiTelecom, and I own a Note 2. When I have my phone settings to EVDO only, it connects to 3g. When I set it to cdma/evdo/lte, it connects to LTE or eHRPD, but never passes any data. I wondered what was wrong with my phone, so I tried getting LTE to work on another phone, but I got the same result. I tried getting LTE once in NY before it was activated there, so I don't know if it's because of my towers or the MVNO, or the phone. I live in the Northern Jersey area, can anybody help me?

[njjdnt]

So I'm on an MVNO named UbiTelecom, and I own a Note 2. When I have my phone settings to EVDO only, it connects to 3g. When I set it to cdma/evdo/lte, it connects to LTE or eHRPD, but never passes any data. I wondered what was wrong with my phone, so I tried getting LTE to work on another phone, but I got the same result. I tried getting LTE once in NY before it was activated there, so I don't know if it's because of my towers or the MVNO, or the phone. I live in the Northern Jersey area, can anybody help me?

You already asked this question a month ago

http://s4gru.com/index.php?/topic/5523-sprint-launches-new-lte-cities-and-spark-markets-2242014/?p=296096

[bobloiy]

You already asked this question a month ago

http://s4gru.com/index.php?/topic/5523-sprint-launches-new-lte-cities-and-spark-markets-2242014/?p=296096

Nobody gave a clear answer to my question, which is why I asked it. There were "maybe it was because of ..." or "it could have been because of ..." but there was never a, "This was because of ..." which left me with answers that could have been correct, but not definite ones.

[JohnHovah]

Nobody gave a clear answer to my question, which is why I asked it. There were "maybe it was because of ..." or "it could have been because of ..." but there was never a, "This was because of ..." which left me with answers that could have been correct, but not definite ones.

 

 

You already asked this question a month ago

http://s4gru.com/index.php?/topic/5523-sprint-launches-new-lte-cities-and-spark-markets-2242014/?p=296096

 

 

It wasn't hard to figure out if you have data or not.  Looking at the UBI site, there are several data options, none of which is unlimited.  http://www.ubitelecom.com/plan/pindex.php  

 

Also, the Note 2 seems to fall under their BYOSD (bring your own sprint device) option and is not officially supported as stated previously.  The best thing to do would be to call and speak with an UBI rep and explain your issue and see if they can do anything on their end.