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Future of Sprint and 800 MHz band (posts moved from Evo 3D forum)

Yeah, that's what I was thinking - ok - time to PM to verify...

PS - Wait.

The Sprint move is old news - http://www.engadget.com/2011/03/16/sprint-direct-connect-will-replace-iden-with-cdma-launch-late-t/

And their first phone with this passed FCC in Apr - http://www.phonearena.com/news/Firs...prints-iDEN-bands-passes-FCC-approval_id17893 aka the Samsung Trender

http://www.phonedog.com/2011/05/26/...-99-unlimited-talk-and-text-plan-on-june-5th/

So the only info here is they've moved up their handset support (engadget said more phones in 2012 if I read correctly) and it's going now from bottom- to top-of-line phones.
 
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Hi guys, sorry out in the field today.

The 800mhz spectrum is just converting iden over to cdma, wimax, and lte. Nothing more. The phone does not really support rev b of cdma2000, but it would be possible, depending on the firmware upgrade.

Sprint shares some spectrum with verizon on the 1900mhz side. Verizon will convert that over to lte in the near future, like less then 4 years. Which means sprint needs to move cdma off the 1900mhz spectrum shared with verizon to another spectrum, like the 800mhz. The 800mhz is also being built out with wimax 2 and lte-a abilities, just don't expect them anytime soon. As soon as the build out is completed, you will be able to use your cdma 800mhz supported phone, ie the evo 3d, in the iden only areas.

After a few years, wimax will replace iden and the same towers will allow lte roaming.

Cdma2000 and gsm is a dead technology, most of the major players have stopped developing it and really stopped production of it. But sprint needs to move off the shared spectrum with verizon, so verizon can move to lte. This will completely expected, part of the leapfrog program.
 
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Yes it does. Propagation loss is proportional to the square of the frequency. This means that if the frequency used is lowered by 1/2 then the loss will be decreased by a factor of 4. In addition to that, a lower frequency means a longer wavelength, which in turn means that you are less likely to have as much loss through excitation of the atoms of surrounding objects.

Neither of those losses are the only elements that comes into play in the overall link budget and they are not likely the dominant terms (i.e. multipath effects) so this doesn't mean you will have a 4x improvement in signal strength, but I do expect a noticeable improvement.
No, not really.

I will just have to pull up a chart for this one.
attachment.php


As you can see from the above chart signal fade is depend on the thickness of the building. Your walls maybe thinner but 3000mhz may penetrate better then 800mhz.

As you can see from the chart, signal penetration at this location is about the same at 800 as it is at 1900. Because of the thickness of the walls stops a 800mhz signal while allowing to pass a 1900mhz.
http://descanso.jpl.nasa.gov/Propagation/napex20/vogel2.pdf
The other problem is simple. If you are currently using the 800mhz iden network, you will start using the 800mhz cdma network. If you are using the 1900mhz network, you will not get the 800mhz unless it already exists. They can not allow the 800mhz to be launch next to the 1900mhz. Only in a ver few cases will you see your phone be able to choose between either network, it will be one or the other.
 

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No, not really.

I will just have to pull up a chart for this one.
attachment.php


As you can see from the above chart signal fade is depend on the thickness of the building. Your walls maybe thinner but 3000mhz may penetrate better then 800mhz.

As you can see from the chart, signal penetration at this location is about the same at 800 as it is at 1900. Because of the thickness of the walls stops a 800mhz signal while allowing to pass a 1900mhz.
http://descanso.jpl.nasa.gov/Propagation/napex20/vogel2.pdf
The other problem is simple. If you are currently using the 800mhz iden network, you will start using the 800mhz cdma network. If you are using the 1900mhz network, you will not get the 800mhz unless it already exists. They can not allow the 800mhz to be launch next to the 1900mhz. Only in a ver few cases will you see your phone be able to choose between either network, it will be one or the other.

Not sure what you are looking at but looking at the graph it looks like 800MHz (~13dB loss) has less loss than 1900MHz (~17dB loss). a 4 dB difference represents 2.5x meaning that you get 2.5 times more loss at 1.9GHz vs 800 MHz. Also if you look at the linear trend line present the line is monotonically decreasing as you increase frequency meaning, generally, higher frequency means more loss.

And even ignoring the fading term due to buildings, the propagation loss is still better as I discussed before so in the end 800MHz will give you a better signal strength than 1.9GHz. The degree of how much better will obviously vary with the infinite number of environmental variables.
 
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Not sure what you are looking at but looking at the graph it looks like 800MHz (~13dB loss) has less loss than 1900MHz (~17dB loss). a 4 dB difference represents 2.5x meaning that you get 2.5 times more loss at 1.9GHz vs 800 MHz. Also if you look at the linear trend line present the line is monotonically decreasing as you increase frequency meaning, generally, higher frequency means more loss.

And even ignoring the fading term due to buildings, the propagation loss is still better as I discussed before so in the end 800MHz will give you a better signal strength than 1.9GHz. The degree of how much better will obviously vary with the infinite number of environmental variables.
LOL I do build outs every day, 6 days a week.

Your average fade at 800mhz will be between -10 to -20. Your average fade at 1.9ghz will be about -8 to -21. The reason that they are soo close is because of buildings are usually 5 to 8 inches thick, which blocks 800mhz better then 1.9ghz.

When you say you half the frequency and get 4 times better penetration only works in general, but specifics REAL WORLD effects says that anything between 700mhz to 3ghz will have about the same building fade averaged over the whole cell site.

There is always a huge difference between lab and mathematical testings and real world build outs.
 
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PS to River - any expectation of 3G speed change when they change freqs?

Same crappy network, sorry, could not help myself. Yes you should see a good bump in speed, maybe up to 3.1mbps. But that really depends on how much the network is being used.

The biggie is the 10mhz spread on wimax. With a 10 mhz spread we could see wimax speeds up to 30-40mbps. Could even get up to 50's. Averages should be around 5-15mbps.
 
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LOL I do build outs every day, 6 days a week.

Your average fade at 800mhz will be between -10 to -20. Your average fade at 1.9ghz will be about -8 to -21. The reason that they are soo close is because of buildings are usually 5 to 8 inches thick, which blocks 800mhz better then 1.9ghz.

When you say you half the frequency and get 4 times better penetration only works in general, but specifics REAL WORLD effects says that anything between 700mhz to 3ghz will have about the same building fade averaged over the whole cell site.

There is always a huge difference between lab and mathematical testings and real world build outs.

Your argument is "trust me I do this for a living". I'm sorry I am newer to this forum and you may truly be an expert in the field and may have proven it to the others already but that's not enough for me. It doesn't help that your supporting material seems to contradict you.

The paper you posted as your evidence definitely seems to be pointing in the opposite direction. The conclusion section seems pretty clear to me:

"4) The attenuation into the buildings increased only moderately with frequency in four of the buildings with a mean slope of about 1 to 3 dB/GHz, but increased fastest in the least attenuating building with a mean slope of 6 dB/GHz. The mean slope was near zero for the glass walled MER building."

This says 5 of the 6 building types tested had a moderate to large increase in attenuation due to building penetration as the frequency increased. Am I missing something? This is a "REAL WORLD" test isn't it?

In my first post I had broken up the losses into two parts. I wasn't as clear as I should have been but by propagation loss I am referring to Free Space Path Loss. [URL="http://en.wikipedia.org/wiki/Free-space_path_loss"]http://en.wikipedia.org/wiki/Free-space_path_loss[/URL]
This is a loss that a signal will have as it propagates over free space (air too), without any obstacles in the way (i.e. no buildings). This term is where I got the 4x from and is independent of building penetration.

Ideal != real world, I know. building size, materials, height, etc all make a difference in the real world so I can't make a blanket statement. But its not a stretch to say that generally the higher the frequency the worse off you are from a path loss (includes all losses) perspective, and that means given a fixed amount of power and fixed size you signal strength will also be worse off.

Go ask the military why UHF (~300 MHz) communications is still so critical for them. I'll tell you why, its all about the robustness. I don't need a directional antenna that I have to keep properly pointed (not really an issue at L-Band either), and because it doesn't matter if I am in a dense rain-forest with a thick canopy, in an open desert, or in a building chasing after a terrorist they'll be able to connect.
 
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What's the benefit to us users? :thinking:

I took it as them knowing that certain people might have the EVO3D by the time they have "Network Vision"(Project Leapfrog) rolled out in areas and the multi-mode towers will aid phones with the capability of switching b/w those freq. Last I read it wa slated to have a large chunk done by next few yrs, w/ iDen being shut off hopefully by 2017.

The added freq doesn't mean the EVO3D will support voice/data on CDMA at same time when sprint gets its CDMA 1X Advanced loaded on the towers(which is slated to be 80% complete by 2013). From what ive read phones will still need to have the specific processor that supports SVDO which i don't think the EVO3D does. but I could be wrong.

In other news and slightly side topic, dont forget about June 9th as Clearwire faces the FCC to ask for wider MHz channels.
FCC to consider letting Clearwire use wider channels
 
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I took it as them knowing that certain people might have the EVO3D by the time they have "Network Vision"(Project Leapfrog) rolled out in areas and the multi-mode towers will aid phones with the capability of switching b/w those freq. Last I read it wa slated to have a large chunk done by next few yrs, w/ iDen being shut off hopefully by 2017.

The added freq doesn't mean the EVO3D will support voice/data on CDMA at same time when sprint gets its CDMA 1X Advanced loaded on the towers(which is slated to be 80% complete by 2013). From what ive read phones will still need to have the specific processor that supports SVDO which i don't think the EVO3D does. but I could be wrong.

In other news and slightly side topic, dont forget about June 9th as Clearwire faces the FCC to ask for wider MHz channels.
FCC to consider letting Clearwire use wider channels

2017 for iDen shutdown? :eek::eek::eek::eek::eek::eek: I had heard 2013, but it was a forum post with no corroboration, so could have been completely inaccurate. 2017 seems like a long time to be bleeding iDen money...just wow.

Secondly, I never knew about the Clearwire FCC thing. Intersting. Thanks for the heads up.
 
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2017 for iDen shutdown? :eek::eek::eek::eek::eek::eek: I had heard 2013, but it was a forum post with no corroboration, so could have been completely inaccurate. 2017 seems like a long time to be bleeding iDen money...just wow.

Secondly, I never knew about the Clearwire FCC thing. Intersting. Thanks for the heads up.

Yeah I think the network upgrades(NetworkVision/ProjectLeapfrog) get confused with assuming that when they are complete iDEN is automatically shut down. They have to phase the devices out but can't do so till the network upgrades are complete. It could be earlier than that date very easily, but all depends on the speed of people getting rid of their handsets and upgrading.

Though enough network talk as everything I have said is 2nd or 3rd hand info anyway but seems to be the most reliable from what I've read around too.(which is a lot)

regardless back to EVO3D talk! :)
 
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Which makes complete sense if you ask me. Which is why i was sure to follow up saying that what I was saying was 2nd or even 3rd hand info and could in fact be wrong. lol

I think it is possible that the reason behined '17 is that by '13 ppl will need to be on their but to upgrade their device, and that they will not be supporting said devices from then on out, but give them time to upgrade to new devices till then '('17) and at that point they literally flip the switch and shut the thing off. Again that is pure 100% speculation by me there though trying to figure out reasoning behined that date as I didn't get a chance to ask. If I get an answer to that I'll chime that in.

RiverOfIce might actually know a lil more on this specifically to be quite honest.
 
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...

The added freq doesn't mean the EVO3D will support voice/data on CDMA at same time when sprint gets its CDMA 1X Advanced loaded on the towers(which is slated to be 80% complete by 2013). From what ive read phones will still need to have the specific processor that supports SVDO which i don't think the EVO3D does. but I could be wrong.

...

I think you are right. From looking at the specs for the MSM8660, it does not appear that it supports 1X-Advanced. It's sort of ridiculous though given how hard Qualcomm has been pushing 1X Advanced on carriers and yet, they won't put it in their own top-of-the-line, now in its 3rd generation, smartphone chipset. :eek:
 
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Your argument is "trust me I do this for a living". I'm sorry I am newer to this forum and you may truly be an expert in the field and may have proven it to the others already but that's not enough for me. It doesn't help that your supporting material seems to contradict you.Am I missing something? This is a "REAL WORLD" test isn't it?

Sigh, ok, you win. Of course not what verizon says.

Verizon is willing to trade the 700 mhz spectrum, for 1900mhz spectrum.

Verizon wants to swap spectrum with U.S. Cellular - FierceWireless

I do, do this for a living. I know this better then most people. In a cellualar build out, the 700-800 spectrum is good, but there is alot of places, do to building, lay of land, and tower density, that the upper spectrum is needed.

In the real world, every build out requires different tools. With your 300mhz argument, how many users can use it? what less then 100 users per tower, and how far the towers need to be apart, what 40 miles?

The only thing that is missing from the real world experiment is a full and build out network. I can lay about 150 towers at 1 mile area at 2.5ghz or I can place 1 tower at 800mhz in a mile area, which is going to have better penetration? Given that there is only a 33-3% fade between 800mhz to 2.5ghz, but I can install 150x more towers, the real world build out is a complete and udder dead wash.

Verizon is giving up the 700mhz spectrum, considered the most valuable spectrum, for the 1.9ghz, because of tower placement and build out needs.
 
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i just want sprint to hurry up and get the data connectivity more stable... and availalble.

their network is in disarray...
form day to day... area to area...
I understand they are working on it.. but it is killing me.

in Dallas ftworth texas area:
3G below 100kbs
4G not available at all..

/rant
 
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I just love rumors. Let us look at some facts.

debt due in the next 3 years 4billion
Cost to convert over to lte in the next 3 years 6 billion
Cost to keep clear wire afloat over the next 3 years 3 billion.

Total profit over the last few years 0.

Makes complete sense for them to build out lte when they can bearly afford wimax. and what is going to happen when they do build out lte, itwill perform just like wimax.
 
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