Deployment of LTE on B25

[samwelltarley]

Can anyone kindly give me an idea on Sprint's deployment of LTE over Band 25? I know it's market dependent but going through this site I read some scattered reports of Sprint only deploying 5x5 or 10x10 of Band 25 in some markets. Is this generally true? I would have thought Sprint would have deployed LTE over more of its PCS spectrum given that they own between 35-40MHz in many major markets. Why would they not have gone ahead and move those from 3G to the more spectrally-efficient LTE bands to get more capacity over such a congested network? Your insight is greatly appreciated.

 

Thanks.

[danlodish345]

Can anyone kindly give me an idea on Sprint's deployment of LTE over Band 25? I know it's market dependent but going through this site I read some scattered reports of Sprint only deploying 5x5 or 10x10 of Band 25 in some markets. Is this generally true? I would have thought Sprint would have deployed LTE over more of its PCS spectrum given that they own between 35-40MHz in many major markets. Why would they not have gone ahead and move those from 3G to the more spectrally-efficient LTE bands to get more capacity over such a congested network? Your insight is greatly appreciated.

 

Thanks.

It depends on the market and how much Spectrum Sprint has per market. Its market dependent

 

Sent from my LGLS775 using Tapatalk

[samwelltarley]

It depends on the market and how much Spectrum Sprint has per market. Its market dependent

 

Sent from my LGLS775 using Tapatalk

 

As I said I know it's market dependent. If you want to get specific, what about your market? Or any market that you're well-informed about?

 

For example, they have 30MHz of PCS spectrum in Boston. How much of that has B25 been deployed?

[danlodish345]

As I said I know it's market dependent. If you want to get specific, what about your market? Or any market that you're well-informed about?

 

For example, they have 30MHz of PCS spectrum in Boston. How much of that has B25 been deployed?

I m not well informed enough sorry....i dont know how to answer that...i ll let someone else step in

 

Sent from my LGLS775 using Tapatalk

[ingenium]

In Pittsburgh and some parts of Ohio they have a 10x10 B25 carrier. Other parts of Ohio have 2 5x5 carriers or both a 10x10 and a 5x5.

 

San Francisco is spectrum poor for PCS (Sprint sold a chunk to ATT back into the day), but they just rolled out a second 5x5 B25 carrier there. In most markets they're now rolled out either a second 5x5 B25 carrier or a 10x10 B25 carrier (or in some rare cases both), depending on if they can do spectrum swaps for the C block next to the G block.

 

In SF, they had to drop down to 3 CDMA carriers to do this (1 1x and 2 EVDO). Other markets may allow more CDMA carriers to be on the air, but we know they're willing to drop to 3 and launch a 10x10 in addition to a 5x5 if possible (depends on site spacing, load, etc).

 

Figure each CDMA carrier uses 3 MHz (1.4 FDD plus guard bands). So that's 9 MHz minimum for CDMA. San Francisco only had 20 MHz (I think) plus the 10 mhz G block, so that spectrum is all completely used. In markets with 30 MHz plus the G block, it's possible they'll roll out a 5x5 and later expand it to a 10x10 and a 5x5, or even merge it with the G block to get 15x15 if the equipment is recertified by the FCC.

 

Sent from my Nexus 6P

[Dkoellerwx]

As I said I know it's market dependent. If you want to get specific, what about your market? Or any market that you're well-informed about?

 

For example, they have 30MHz of PCS spectrum in Boston. How much of that has B25 been deployed?

 

Band 25 was initially 5x5 only because it was being deployed solely on the PCS G block, which in most markets was the only greenfield spectrum that Sprint had in PCS. The majority of the PCS spectrum that Sprint owns had been in use for CDMA operations. Over the last two years, Sprint has trimmed CDMA (EVDO) carriers allowing them to deploy a second 5x5 carrier, or in some markets increase to a 10x10 carrier. In a few sections of a few select markets they have a 10x10 carrier + a 5x5 carrier.

[samwelltarley]

In Pittsburgh and some parts of Ohio they have a 10x10 B25 carrier. Other parts of Ohio have 2 5x5 carriers or both a 10x10 and a 5x5.

 

San Francisco is spectrum poor for PCS (Sprint sold a chunk to ATT back into the day), but they just rolled out a second 5x5 B25 carrier there. In most markets they're now rolled out either a second 5x5 B25 carrier or a 10x10 B25 carrier (or in some rare cases both), depending on if they can do spectrum swaps for the C block next to the G block.

 

In SF, they had to drop down to 3 CDMA carriers to do this (1 1x and 2 EVDO). Other markets may allow more CDMA carriers to be on the air, but we know they're willing to drop to 3 and launch a 10x10 in addition to a 5x5 if possible (depends on site spacing, load, etc).

 

Figure each CDMA carrier uses 3 MHz (1.4 FDD plus guard bands). So that's 9 MHz minimum for CDMA. San Francisco only had 20 MHz (I think) plus the 10 mhz G block, so that spectrum is all completely used. In markets with 30 MHz plus the G block, it's possible they'll roll out a 5x5 and later expand it to a 10x10 and a 5x5, or even merge it with the G block to get 15x15 if the equipment is recertified by the FCC.

 

Sent from my Nexus 6P

 

thank you and dkoellerwx for the informative color. It answers a lot of my questions. So Sprint rolled out LTE on B25 on the 5x5 G block first. Then selective activate more over the A-F blocks, leaving 3 CDMA carriers (10MHz). Is it then fair to say in most markets, Sprint has deployed B25 on pretty much all PCS spectrum save for the 10MHz minimum to support 3 CDMA ccarriers?

[Dkoellerwx]

thank you and dkoellerwx for the informative color. It answers a lot of my questions. So Sprint rolled out LTE on B25 on the 5x5 G block first. Then selective activate more over the A-F blocks, leaving 3 CDMA carriers (10MHz). Is it then fair to say in most markets, Sprint has deployed B25 on pretty much all PCS spectrum save for the 10MHz minimum to support 3 CDMA ccarriers?

 

Some markets still require more than 10MHz for CDMA. I can't name them off the top of my head though. I do know they are still working on the second B25 carrier in New York City, and there may be other places where it is not live yet.

 

I'm going to use Kansas City as an example, because that is the market I am most familiar with. Sprint earlier this year cleared some of their A Block spectrum for a second 5x5 LTE carrier. However, I believe they own 30MHz of spectrum + the G Block. So that still leaves 20MHz in use for CDMA operations. 

[WiWavelength]

Is it then fair to say in most markets, Sprint has deployed B25 on pretty much all PCS spectrum save for the 10MHz minimum to support 3 CDMA ccarriers?

 

No.

 

As others have posted, band 25 deployment outside of the PCS G block is highly market or even site dependent.

 

We have individual market deployment and additional carrier/EARFCN threads to discuss these vagaries.  So, we probably will not continue this discussion as an omnibus.  Please direct research and questions to those resources.

 

http://s4gru.com/index.php?/blog/1/entry-27-spectrum-analysisdoes-sprint-have-more-options-for-additional-lte-carriers/

http://s4gru.com/index.php?/blog/1/entry-394-columbus-8640-the-age-of-10-mhz-fdd-discovery/

http://s4gru.com/index.php?/topic/5454-network-vision-and-spark-earfcn-logging-thread/

http://s4gru.com/index.php?/topic/6891-b25-2nd-carrier-info/

 

AJ

[samwelltarley]

No.

 

As others have posted, band 25 deployment outside of the PCS G block is highly market or even site dependent.

 

We have individual market deployment and additional carrier/EARFCN threads to discuss these vagaries.  So, we probably will not continue this discussion as an omnibus.  Please direct research and questions to those resources.

 

http://s4gru.com/index.php?/blog/1/entry-27-spectrum-analysisdoes-sprint-have-more-options-for-additional-lte-carriers/

http://s4gru.com/index.php?/blog/1/entry-394-columbus-8640-the-age-of-10-mhz-fdd-discovery/

http://s4gru.com/index.php?/topic/5454-network-vision-and-spark-earfcn-logging-thread/

http://s4gru.com/index.php?/topic/6891-b25-2nd-carrier-info/

 

AJ

 

So I caught up with your suggested reading and they are indeed a great collection. Thanks for pointing me there. Now having confirmed a number of my suspicion, I'd like to ask the experts that be to contemplate/speculate on the following general network architectural questions (feel free to move this thread to any other better-fitted thread):

 

- why hasn't Sprint refarmed more of the PCS spectrum to LTE faster: after they deployed B25 on the G block, they could've deployed at least another 5x5 in almost all markets right away to solve the network congestion everyone is complaining about. I see that they've deployed the second channel in some markets, (some are even 15x15 B25 channel) but why haven't they done it more widely and earlier? I can't imagine there is still that much demand for 3G spectrum in 2016. An engineer once told me that LTE doesn't hold the airlink as well as EVDO signals and so refarming too much PCS spectrum to LTE would cause unacceptable coverage holes until B41 or B26 can come to the rescue. Is that true? If so, then is it the reason why they have to retain so much legacy 3G deployment?

 

- When they deploy a second 5x5 B25 channel on top of the existing 5x5 block G, obviously that increases capacity of the network, but would that increase max speed to the users? i.e. Can a regular phone like iPhone 6S aggregate two B25 channels to create a wider channel like it CAs 2 B41 channels? That would help me understand the significance of deploying contiguous B25 channels versus discrete ones.

 

- why had Sprint refarmed the PCS spectrum to LTE the way it had? In all of the 24 "original" markets, they own contiguous 30MHz of A block or B block, plus the 10MHz G block. Their most natural LTE architectural should have been deploy 10x10 channel (and then perhaps 15x15 if circcumstances permit) on those contiguous blocks and then leave the G block for three 1x channels.

 

Best,

Biggest nerd of all time

[WiWavelength]

- why had Sprint refarmed the PCS spectrum to LTE the way it had? In all of the 24 "original" markets, they own contiguous 30MHz of A block or B block, plus the 10MHz G block. Their most natural LTE architectural should have been deploy 10x10 channel (and then perhaps 15x15 if circcumstances permit) on those contiguous blocks and then leave the G block for three 1x channels.

 

This is the quickest question to answer.

 

Band class 1 in 3GPP2 standards is limited to the traditional PCS A-F blocks.  CDMA2000 operations in the PCS G block require band class 14.  Sprint dabbled with the idea of band class 14, but it could have necessitated replacing all CDMA2000 devices on the network, not to mention, being the only major operator using band class 14.

 

AJ

[Dkoellerwx]

- why hasn't Sprint refarmed more of the PCS spectrum to LTE faster: after they deployed B25 on the G block, they could've deployed at least another 5x5 in almost all markets right away to solve the network congestion everyone is complaining about. I see that they've deployed the second channel in some markets, (some are even 15x15 B25 channel) but why haven't they done it more widely and earlier? I can't imagine there is still that much demand for 3G spectrum in 2016. An engineer once told me that LTE doesn't hold the airlink as well as EVDO signals and so refarming too much PCS spectrum to LTE would cause unacceptable coverage holes until B41 or B26 can come to the rescue. Is that true? If so, then is it the reason why they have to retain so much legacy 3G deployment?

 

 

3G usage was still fairly high, especially until B26 was widely deployed and optimized. Where there was sufficient spectrum, the second carrier was brought online relatively quickly. Trimming EVDO has taken quite some time, usage is still higher than you might expect. 

 

 

- When they deploy a second 5x5 B25 channel on top of the existing 5x5 block G, obviously that increases capacity of the network, but would that increase max speed to the users? i.e. Can a regular phone like iPhone 6S aggregate two B25 channels to create a wider channel like it CAs 2 B41 channels? That would help me understand the significance of deploying contiguous B25 channels versus discrete ones.

 

2 5x5 carriers increase capacity but not peak speeds. Currently, B25 CA is not enabled, and only a very few devices could take advantage if it was. It is in the plan, how soon it will be I do not know.

 

10x10 carriers increase capacity and top speeds, and where they can Sprint has increased their carriers to 10x10.

[Tengen31]

Can anyone kindly give me an idea on Sprint's deployment of LTE over Band 25? I know it's market dependent but going through this site I read some scattered reports of Sprint only deploying 5x5 or 10x10 of Band 25 in some markets. Is this generally true? I would have thought Sprint would have deployed LTE over more of its PCS spectrum given that they own between 35-40MHz in many major markets. Why would they not have gone ahead and move those from 3G to the more spectrally-efficient LTE bands to get more capacity over such a congested network? Your insight is greatly appreciated.

 

Thanks.

The spectrum has to be contiguous to do any widen. Thats why they are swapping with att, vzw and tmobile to get that. There equipment is also not  (yet) certified or approved for 15x15 or 20x20. There are places they can do it tho, just needs to be certified first.

Edited October 18, 2016 by Dkoellerwx
There Their They're

[caspar347]

In many places, site density is so low and so few 8T8Rs have been deployed (or maybe they just haven't been optimized since initial deployment...?) that B26 is deployed with the same range as B25 which keeps all data use on the far edges of cells on EVDO.