Network Vision/LTE - Chicago Market

[Fraydog]

There should be only HSPA in band C... But it could well be that TMUS is also cramming GSM channels into the guard bands built into HSPA.

 

Knowing GSM interferes like a mother (ask AJ about it), that seems like the likely possibility.

[tommym65]

How can we verify?  Would Sprint verify? And if T-Mobile is the cause of the interference what will happen?

 

Sprint is not likely to comment, for legal reasons, unless they file an FCC complaint or a lawsuit.  What we need is someone with a spectrum analyzer to go into the city and look at the G Block and the adjacent frequencies. Hypothetically, if TMO is the cause, they would get slapped with some very hefty fines.

[tommym65]

. . .  According to AJ and other sources, Sprint has initially deployed 1900 LTE on PCS Block G (1910-1915MHz and 1990-1995MHz). PCS Block C (1895-1910MHz and 1975-1990MHz) falls directly below Block G, and is operated by T-Mobile in Chicago. The frequencies above Block G are not mobile communication, and I have no idea what they are used for. So, is the ultra-urgent TMO LTE deployment in Block C somehow responsible for the Sprint LTE mess? Or is something going on in the frequencies above 1995, and is THAT somehow responsible?

 

 

And a later note: TMO also occupies all of C Block in the St. Louis market, but does not have the C Block band adjacent to G Block in Minneapolis.  What has their experience been?

 

See the chart at:

 

http://www.google.com/imgres?imgurl=http://2.bp.blogspot.com/-pj4vuAanG1g/Uc3Hf4eyCdI/AAAAAAAAAUQ/4BwgaajgDzQ/s1102/uscellular_chicago_pcs.JPG&imgrefurl=http://allnetlabs.blogspot.com/&h=614&w=1102&sz=200&tbnid=_b503cgiADZAdM:&tbnh=90&tbnw=162&zoom=1&usg=__9nCMl-2pHzdJqXpAhxhNIcYcMn0=&docid=rWUks6D4xSLtDM&sa=X&ei=_Vd8UofCDsTmsATghYDQCw&ved=0CGQQ9QEwBg

[Fraydog]

STL signal to noise ratios have been normal.

[Vince]

He'll, I don't mind buying a spectrum analyzer, problem is, I wouldn't know what to look for.

[Joeynach]

Screenshot_2013-11-07-19-27-58.png

 

I am currently in downtown Colorado Springs, and the LTE screenshot I am posting above is a site about 1.7 miles east of me (although the 1xRTT address is offset to the west), based on the latest NV map update. The RSRP is poor, but the SNR is very good. Speeds between .6 and 2.0 down, .25 and 1 up, ping low 100's. Technically, Colo Springs is pre-launch, but the SNR number is fairly typical of what I have seen in recent trips to California, Missouri, and Colorado

 

That said, some comments on the Great Chicago SNR Debacle. One of the customers at the user group meeting that I am attending operates an extensive, combined wireless/wired ISP on a Caribbean island. I showed him the "Red Line" screen shot from earlier today (-55 dBm RSPR, 0.1 dB SNR), and based on his experience, his immediate comment was that there was MAJOR interference from an adjacent frequency, and that whoever is responsible is violating the law. Mobile phones are very good at cutting through noise (my phrase) on the frequencies they are programmed to receive, but cannot not cope well with noise on either side of a given frequency.

 

Which leads to some questions: According to AJ and other sources, Sprint has initially deployed 1900 LTE on PCS Block G (1910-1915MHz and 1990-1995MHz). PCS Block C (1895-1910MHz and 1975-1990MHz) falls directly below Block G, and is operated by T-Mobile in Chicago. The frequencies above Block G are not mobile communication, and I have no idea what they are used for. So, is the ultra-urgent TMO LTE deployment in Block C somehow responsible for the Sprint LTE mess? Or is something going on in the frequencies above 1995, and is THAT somehow responsible?

 

The Sprint D and E blocks are voice/CDMA at this time, and it is not likely that they would be impacted by the same interference that might affect LTE in the G Block. And as far as we know, Sprint hasn't started using, at least at full power, the USCC segment of Block B, so that probably isn't causing a problem, and Verizon (which owns the rest of the B block) hasn't done anything radical that we know of, so that probably isn't the cause.

 

Someone way earlier in this thread asked if TMO might be the cause of Sprint's Chicago LTE problem. Based on the spectrum allocation and on TMO's ultra-aggressive LTE deployment, the answer may very well be "Yes!!!!!"

 

FWIW

This is some seriously good stuff and some serious acquisition of malpractice.  The symptoms of band interference match exactly what we are dealing with here with metro wide degraded SNR, even when literally ontop of a tower.  Though what exactly are we supposed to do with this kind of information now?  I doubt SprintCare would be any assistance, this is way above any CS agent's pay grade, this is call your lawyers and call the FCC type stuff.

[Vince]

Anyone know a good one to buy for a decent price? Links?

[tommym65]

Anyone know a good one to buy for a decent price? Links?

 

Digiblur recently bought one, I think there is a thread, but don't have a clue how to find it.  PM him???

[Fraydog]

Yeah, I suspect Sprint won't say anything, what will likely happen is the problems will suddenly cease because of actions happening at a level far above our pay grade.

[lilotimz]

Anyone know a good one to buy for a decent price? Links?

 

http://s4gru.com/index.php?/topic/4455-shopping-for-an-spectrum-analyzer-rf-explorer/

[Vince]

This is some good stuff, folks. Problem solving at work. It's a shame that it takes a handful of people on a forum to diagnose what their network issues are. A multi-billion dollar company in the middle of their biggest network upgrade in history, teams of engineers across the country, and it takes a forum to figure it out. ????

[Fraydog]

This is some good stuff, folks. Problem solving at work. It's a shame that it takes a handful of people on a forum to diagnose what their network issues are. A multi-billion dollar company in the middle of their biggest network upgrade in history, teams of engineers across the country, and it takes a forum to figure it out.

I suspect Sprint knows what the issue is, I just don't think they will confirm what it is.

[Vince]

I suspect Sprint knows what the issue is, I just don't think they will confirm what it is.

 

Right. There might even be impeding legal action. Who knows. They'll never come out and admit it, assuming this is the cause of slow speeds here.

[bucdenny]

Yeah, I suspect Sprint won't say anything, what will likely happen is the problems will suddenly cease because of actions happening at a level far above our pay grade.

 

If they don't do anything, more and more customers are jumping ships with 100kb LTE speeds. I think someone needs to prove in fact it is an interference and tweet that to Mr Son.  Maybe he will do something.

[Fraydog]

I'd rather let Hesse handle whatever is going on. I have faith here.

[bucdenny]

Hesse is not active on Twitter.  Imagine reporting such an issue to John Legere on his Twitter, I bet we would have a response,

[Vince]

Hesse is not active on Twitter. Imagine reporting such an issue to John Legere on his Twitter, I bet we would have a response,

I got Legere to fix a nationwide network problem over the summer when I was on a one-month trial on tmus. He reads twitter and responds to customers daily. We need something like that.

[tongboy]

This actually would make sense T-Mobile likely has in the same vicinity as sprint. That's why we are seeing a 55 RSRP (insane signal strength) but horrid SNR.

 

Sent from my HTCONE using Tapatalk

 

 

[Vince]

This actually would make sense T-Mobile likely has in the same vicinity as sprint. That's why we are seeing a 55 RSRP (insane signal strength) but horrid SNR.

 

Sent from my HTCONE using Tapatalk

It's the best theory that we have to date. Now, it just needs to be proven and fixed. Even though it has been an ongoing issue for approximately 6-8 weeks, we have to just assume Sprint knows about this (if it's truly the problem). Now we just play the waiting game.

[tongboy]

Although it probably wouldn't prove anything I would like to see a spectrum analyzer to see if there is interference from a neighboring band. I'm not sure if I can but I will see if I can fire one up at work. No promises though.

 

Sent from my HTCONE using Tapatalk

 

 

[bucdenny]

Although it probably wouldn't prove anything I would like to see a spectrum analyzer to see if there is interference from a neighboring band. I'm not sure if I can but I will see if I can fire one up at work. No promises though.

 

Sent from my HTCONE using Tapatalk

 

Post on Youtube please if indeed T-Mobile is bleeding over.

[tongboy]

If I can get access to a SA and I can check the band please everyone keep in mind that even if it shows that there is signal in the guard band between the Sprint G block and T-Mobile it probably won't prove that T-Mobile is the cause and it for sure won't prove that T-Mobile is intentionally doing it. I really don't want an industry event created from the picture.

 

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[hayzooos]

I responded to two people (one about developer phones and another about carrieriq) in the same post and the whole thing got deleted? Dang, pretty tight around here, eh?

[tongboy]

I apologize everyone. The team I needed to speak with to gain access to a SA isn't here today. I will try again on Monday.

 

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[Fraydog]

Guys, just let Sprint investigate the problem.

 

No need for anyone on here to do anything. Please.