Sprint TD-LTE 2500/2600mhz Discussion

[Keitarou]

Lastly, just to be clear, LTE Advanced carrier aggregation will not allow Sprint to aggregate its LTE carriers with Clearwire's TD-LTE carriers.  Only LTE to LTE and TD-LTE to TD-LTE carrier aggregation (but not a mix) will be possible.

Having multiple variation of LTE, is that cost effective? Wouldn't it make sense to either go TD-LTE or just LTE for all spectrum Sprint/Clearwire hold? Shouldn't Sprint make a decision as to which one will be the last one standing? Or maybe LTE Advance is what will be the last one standing phasing out TD-LTE/LTE?

[WiWavelength]

Having multiple variation of LTE, is that cost effective? Wouldn't it make sense to either go TD-LTE or just LTE for all spectrum Sprint/Clearwire hold? Shouldn't Sprint make a decision as to which one will be the last one standing? Or maybe LTE Advance is what will be the last one standing phasing out TD-LTE/LTE?

 

Nope.  BRS/EBS 2600 MHz is set up for TDD, not FDD.  Simple as that.

 

AJ

[ChadBroChillz]

Having multiple variation of LTE, is that cost effective? Wouldn't it make sense to either go TD-LTE or just LTE for all spectrum Sprint/Clearwire hold? Shouldn't Sprint make a decision as to which one will be the last one standing? Or maybe LTE Advance is what will be the last one standing phasing out TD-LTE/LTE?

 

Their PCS and SMR are paired, while the 2.5Ghz is unpaired. I do not believe their will be a problem. From my understanding, NV is technology independent. Sprint can deploy TD-LTE/LTE/CDMA all on the same NV cell site.

 

Also, carrier aggregation of the TD-LTE spectrum would give them more than enough capacity and speed to win any pissing contest.

 

[ericdabbs]

Now, if any of those carriers currently are or will be cut back to 5 MHz FDD, then the WiMAX spectrum utilization drops accordingly.

 

AJ

 

Do you mean 5 MHz TDD?  I know from looking at my Wimax engineering menu on the Photon (phone dialer ##DATA# then go to "Wimax" -> "Center Frequency" and "Bandwidth") there are a ton of 5 MHz TDD carriers listed.  I think it would be wise for Sprint and Clearwire to start consider configuring the Wimax network on cell sites to use 5 MHz TDD carriers so that it lowers the Wimax spectrum utilization and free up more spectrum for TD-LTE.  Since Sprint has started updating the terms and conditions for Wimax users, this would be a good step in the right direction.  Hopefully there would be planning to ensure the relocation of Wimax network would free up 20 MHz of contiguous spectrum for TD-LTE.

[WiWavelength]

Do you mean 5 MHz TDD?  I know from looking at my Wimax engineering menu on the Photon (phone dialer ##DATA# then go to "Wimax" -> "Center Frequency" and "Bandwidth") there are a ton of 5 MHz TDD carriers listed.  I think it would be wise for Sprint and Clearwire to start consider configuring the Wimax network on cell sites to use 5 MHz TDD carriers so that it lowers the Wimax spectrum utilization and free up more spectrum for TD-LTE.  Since Sprint has started updating the terms and conditions for Wimax users, this would be a good step in the right direction.  Hopefully there would be planning to ensure the relocation of Wimax network would free up 20 MHz of contiguous spectrum for TD-LTE.

 

Yes, indeed, I did mean TDD.  When typing out FDD and TDD a dozen times a day for free, I am bound to transpose them accidentally on occasion.

 

As for 5 MHz TDD WiMAX carriers, I have found only one, and that was via my spectrum analyzer.  It is interesting to know that many others exist.  However, that could be highly market and spectrum dependent.

 

Cutting back WiMAX carriers to 5 MHz TDD and refarming for TD-LTE may not be necessary.  If a market already has any 20 MHz TDD contiguous blocks of spectrum available, then Clearwire is already set for now.  Conversely, because of the potentially fragmented nature of leased EBS spectrum, cutting back to WiMAX 5 MHz TDD carriers may accomplish nothing in the way of freeing up contiguous spectrum.  

 

AJ

[bigsnake49]

Clearwire WiMAX is definitely using differently assigned carriers on adjacent sectors/sites.  If all carriers are 10 MHz TDD, then that means at least 30 MHz utilization per site, and probably 90-120 MHz utilization per frequency reuse cluster.  Now, if any of those carriers currently are or will be cut back to 5 MHz FDD, then the WiMAX spectrum utilization drops accordingly.

 

The non unity frequency reuse could be due to regulatory or technical concerns.  At least one poster here has called Clearwire "lazy" for doing so.  But no one has stepped up with any legitimate evidence to support that assertion.  Instead, by using non unity frequency reuse, WiMAX gets better sector and cell edge performance, since co channel interference becomes almost eradicated.

 

AJ

 

Yes, non-unity frequency reuse allows you to not have to worry about cell edge performance. You basically don't have to tune the network if you're using 10MHz sector channels and 30MHz per site.

[WiWavelength]

Yes, non-unity frequency reuse allows you to not have to worry about cell edge performance. You basically don't have to tune the network if you're using 10MHz sector channels and 30MHz per site.

 

It does not matter how you "tune" the network.  With unity frequency reuse, you are always going to get worse sector and cell edge performance because of co channel interference or weak signal strength -- pick your poison.  Now, CDMA1X avoids that problem to a great degree through soft/softer handoff; not to mention, the voice/data rates being pumped through CDMA1X are well below the Shannon bound.  The same is definitely not true for WiMAX and LTE.

 

AJ

[bigsnake49]

It does not matter how you "tune" the network.  With unity frequency reuse, you are always going to get worse sector and cell edge performance because of co channel interference or weak signal strength -- pick your poison.  Now, CDMA1X avoids that problem to a great degree through soft/softer handoff; not to mention, the voice/data rates being pumped through CDMA1X are well below the Shannon bound.  The same is definitely not true for WiMAX and LTE.

 

AJ

 

There are lot of techniques to improve cell edge performance. Interference cancellation, subcarrier coordination between sites, etc. I don't remember how many of these LTE employs.

[WiWavelength]

There are lot of techniques to improve cell edge performance. Interference cancellation, subcarrier coordination between sites, etc. I don't remember how many of these LTE employs.

 

All of those reduce throughput, which is the criterion most would use to define "performance."  At sector and cell edge, there is no such thing as a free lunch.

 

AJ

[bigsnake49]

All of those reduce throughput, which is the criterion most would use to define "performance."  At sector and cell edge, there is no such thing as a free lunch.

 

AJ

 

Well, no matter whether you unity or non-unity frequency reuse, you will have reduced performance at cell edge. All thse methods are used so that your throughput incereases vs not having them.

[ericdabbs]

Yes, indeed, I did mean TDD.  When typing out FDD and TDD a dozen times a day for free, I am bound to transpose them accidentally on occasion.

 

As for 5 MHz TDD WiMAX carriers, I have found only one, and that was via my spectrum analyzer.  It is interesting to know that many others exist.  However, that could be highly market and spectrum dependent.

 

Cutting back WiMAX carriers to 5 MHz TDD and refarming for TD-LTE may not be necessary.  If a market already has any 20 MHz TDD contiguous blocks of spectrum available, then Clearwire is already set for now.  Conversely, because of the potentially fragmented nature of leased EBS spectrum, cutting back to WiMAX 5 MHz TDD carriers may accomplish nothing in the way of freeing up contiguous spectrum.  

 

AJ

 

Here is a snapshot of the Wimax carriers that can be accessed on the Moto Photon.  Looking at the BRS/EBS chart, it appears that there are a decent amount of 5 MHz TDD carriers in the BRS band with a few 10 MHz TDD carriers in BRS.  

 

I wonder if Clearwire's plan going forward is to utilize the BRS spectrum whereever possible to deploy one or two 20 MHz TDD carriers of TD-LTE and use the EBS spectrum to sustain their Wimax network with 5 or 10 MHz TDD carriers.

[WiWavelength]

Thanks, Eric.  I have never before seen the Motorola Photon WiMAX engineering screen, but it may be the best of the bunch.  When I get a chance, I will drop the center frequency and bandwidth data into a spreadsheet, then cross reference against the BRS/EBS band plan.  This could be interesting.

 

AJ

[WiWavelength]

Eric, I started my WiMAX center frequency vs carrier bandwidth data dump into a spreadsheet.  Egads, man!  There in Southern California, you are like a WiMAX porn star.  You have been with way too many different sites.  You are damaged goods now.

 

 

AJ

[ericdabbs]

AJ, looking forward to seeing your spreadsheet on this information and your thoughts.  I counted and there are 57 Center Frequencies in that screenshot that I can connect to.  I wonder if you can detect any trends as to Clearwire's thinking with their frequency and bandwidth Wimax deployment.

 

Believe me I will jump off of Wimax onto LTE as soon as the Note 3 comes out .  I can't take this phone anymore.  The stock rom on the Photon is still buggy on Gingerbread and was left out in the cold to die .

[ab30494]

on clearwire's coverage map. it shows i have coverage.

 

http://www.clear.com/coverage

 Omaha,NE and council bluffs, IA

 

even though it isn't one of the cities listed. would we still get lte from clear?

 

 

[S4GRU]

on clearwire's coverage map. it shows i have coverage.

 

http://www.clear.com/coverage

Omaha,NE and council bluffs, IA

 

even though it isn't one of the cities listed. would we still get lte from clear?

 

 

 

No. Omaha has WiMax Protection Sites. There are currently no plans to convert them to TD-LTE. However, when Sprint/SoftBank take over Clearwire, all the plans could change.

 

Robert from Note 2 using Tapatalk 4 Beta

 

 

[ab30494]

No. Omaha has WiMax Protection Sites. There are currently no plans to convert them to TD-LTE. However, when Sprint/SoftBank take over Clearwire, all the plans could change.

 

Robert from Note 2 using Tapatalk 4 Beta

 

ok thank you.

 

prob dont need it as much here anyway, Omaha inst really that dense. should be fine with 1900, and 800 once that rolls out. 

[maximus1987/lou99]

This is why it is important for Sprint to keep unlimited data.

 

I disagree. Having "unlimited" doesn't properly convey the value that Sprint is providing.

Instead, Sprint should, and probably will, have caps like 10 GB or 20 GB.

 

Then, someone with 4 GB on Verizon paying $110 will look at someone on Sprint with 20GB also paying $110, and they'll switch.

[tmiw]

I disagree. Having "unlimited" doesn't properly convey the value that Sprint is providing.

Instead, Sprint should, and probably will, have caps like 10 GB or 20 GB.

 

Then, someone with 4 GB on Verizon paying $110 will look at someone on Sprint with 20GB also paying $110, and they'll switch.

 

I would almost be fine with losing "unlimited" as long as pricing remained reasonable and as long as tethering was no longer an extra cost option.

[maximus1987/lou99]

I would almost be fine with losing "unlimited" as long as pricing remained reasonable and as long as tethering was no longer an extra cost option.

 

The only reason why tethering is extra today is because you get unlimited non-tether data.

Unlimited tethering would destroy even the NV network.

[tmiw]

The only reason why tethering is extra today is because you get unlimited non-tether data.

Unlimited tethering would destroy even the NV network.

 

Yep, which is why I understand why it costs extra. If there's no longer unlimited though, there's not really justification for tethering not using the same data that you're already paying for.

[maximus1987/lou99]

Yep, which is why I understand why it costs extra. If there's no longer unlimited though, there's not really justification for tethering not using the same data that you're already paying for.

 

I agree. It's so funny that people were so righteously indignant when ATT still had the unlimited data and they charged extra for tethering.

I couldn't do that with a straight face.

[NGeorge]

Does anyone know how many sites Clear has by itself?

 

Seems to me that by acquiring Clearwire, they are getting themselves into a bit of a Nextel situation, taking on additional sites that they don't really need, increasing their costs.

 

I'm assuming that any 2.5 LTE (and possibly WiMax for backwards compatibility) will be deployed on existing Sprint sites to reduce expenses from multiple leases etc... coupled with the fact that most Clear sites are situated MUCH lower on the tower than the Sprint sites, it seems like would only make sense... Use only the Clear sites that are sitting in Sprint dead zones, and upgrade the other sites directly onto Sprint sites (I seem to remember seeing a slide about this when NV was first proposed, but it never happened--they changed the story to doing it with LightSquared, then never seemed to mention it again... I believe a few of the LightSquared sites were even completed)... of course they didn't do this with Nextel, so we'll see if they do it this time... the only difference being is that it will be a lot easier this time since all the new NV gear can take on LTE at 2.5, and even WiMax with the software defined radios...

[DaQue]

I'm interested what happens to a couple of sites near me. One is a Sprint site on a billboard not far from here in front of a Save A Lot grocery store. Only Sprint is there. Behind the store there is a large tower with multiple vendors including Clearwire Wimax.

 

On the issue of Clearwire being lower that may be a good thing. They can cram the towers closer to getter for lower number of users per tower. Many of the towers around here have the top spots empty and a crowd lower. It seems to be a race to the bottom of the tower.

[WiWavelength]

the only difference being is that it will be a lot easier this time since all the new NV gear can take on LTE at 2.5, and even WiMax with the software defined radios...

 

No, that is not accurate.  Any TD-LTE 2600 deployment on Sprint sites will require additional RRUs and separate panels.

 

AJ