LTE Plus / Enhanced LTE (was "Sprint Spark" - Official Name for the Tri-Band Network)

[waterbound]

With the testing I have completed I am starting to believe the LTE signal issue EVO specific, at least in the area I tested in Annapolis, MD.

 

Myself and a co-worker drove a couple of miles away to a 'known' good 4G area, he with his GS3 and my EVO 4G LTE. We are both updated with latest firmware and radios etc.

 

In our 1/2 hour drive, he picked up LTE twice and locked on for almost the entire time. I picked up a 4G 'blip' once during the test 1/2 hour and by 'blip' it said 4G and was gone before I could verify anything.

 

I tried to chnage from CDMA to CDMA/LTE, LTE only and every combination I could think of and could never connect while he connected and maintained with no issues and pulled about 25mb down on average for most of the drive.

 

I am using apps Network and CDMA field test along with airplane mode toggle between various settings. The only signal I ever saw was Evdo RevA. If I used airplane to toggle it seemd to take forever to get a CDMA signal back. The tower we drove by was a known completed 3G/4G tower according to the interactive maps on the site here.

 

The tower information howing completed 3G/4G:

DC03XC562

38.978218252223726, -76.49302135773709,

9-99 Church Cir, Annapolis, MD 21401, USA

Sprint Market: Baltimore

NV Complete: 3G/4G

OEM: ALU

RF Switch: DC-HANOVER-MSC_2

 

Th troubling part is that he was able to connect to this site a long time before we were there, maybe close to 3-3.5 miles away so he I am assuming he connected to another site that isn't showing up on this completed site?

 

I attached the log files from CDMA field test application if anyone wants to look at them, one is the log and the other is the KML which you can open easily in http://www.gpsvisualizer.com just by browsing to the saved file and it will open in Google Maps.

 

I was trying to deceipher in the log which and at what time I hit the 4G for a fraction of a second by looking at the BSID, SID and RSSI. I thought the BSID was the number that matched up to the above number 'DC03XC562' but no where is the log is anything close to that number.

 

If anyone can shed some light on how to read the log and coorelate to anything useful, please let me know! Otherwise I am waiting a few weeks to see if things improve or assume its an EVO thing and move on.

 

I am rooted an have tried a few ROMS, stock, CM10 and ports of JB, same as the GS3 user but starting to think there is something inherantly wrong at lease with the software on the EVO, at least mine. I also live in between two towers that are about 1.5 miles aways from me and have never seen any 4G but then again, they also dont show as completed on this interactive map so not extecting to see it there.

 

Thanks-

BSlocation.zip

[xenadu]

FYI: on the iPhone, if you go into the debug screen, then hold the power button until the Slide to Power Off message appears, but do not power off, just hold the home button for a few seconds. This will force-quit the debug screen and leave your status bar showing the numeric signal meter instead of bars permanently.

 

To return, just re-enter debug mode then hit the home button to exit like normal. You can also tap on the indicator to switch between bars and numeric.

[Proxcee]

I noticed something a little odd when I ran speed tests in two different parts of town. I managed to find the tower I connect to for LTE using dBm as an indicator. This is what I noticed:

 

In the first pair of screenshots I get about 10 megs down with a -87dBm...

 

<br />

 

 

...in a different part of town I got 26 megs down with a -85 dBm...

 

 

 

 

Can anyone help make sense of this for me? Does -2dbm make that much difference? Maybe its noise ratio? Maybe its something about the backhaul at each site? Not sure what to think at this point. Thanks for your input.

[S4GRU]

I noticed something a little odd when I ran speed tests in two different parts of town. I managed to find the tower I connect to for LTE using dBm as an indicator. This is what I noticed:

 

In the first pair of screenshots I get about 10 megs down with a -87dBm...

 

...in a different part of town I got 26 megs down with a -85 dBm...

 

Can anyone help make sense of this for me? Does -2dbm make that much difference? Maybe its noise ratio? Maybe its something about the backhaul at each site? Not sure what to think at this point. Thanks for your input.

 

RSRQ could be a factor. The better result was with a better quality signal. But most likely it was just a network anomaly. It is unlikely it will keep repeating itself.

 

Robert

[Proxcee]

RSRQ could be a factor. The better result was with a better quality signal. But most likely it was just a network anomaly. It is unlikely it will keep repeating itself.

 

Robert

 

By anomaly do you mean the difference in speeds or one site over another? (lower speed site vs. the higher speed site)?

 

Now that I am thinking about it....the lower speed site is the one I am more than likely connected to at home (2.1) miles away since it is the closest. I get on average a -94 rsrp which gives me approx. 7-9 megs down. I pull up maybe about 100 ft. from the tower, get a -87 rsrp and only pull 10 megs. Since LTE signal is more distance oriented I guess I just thought that if I was right in front of the site that speeds would be much better than the speeds that I get when I am 2 miles away.

 

Also....does a higher noise ratio = better connection/speed?

[S4GRU]

Also....does a higher noise ratio = better connection/speed?

 

A "better" noise ratio = better connection, which should result in a higher speed.

 

Robert

[WiWavelength]

Since LTE signal is more distance oriented I guess I just thought that if I was right in front of the site that speeds would be much better than the speeds that I get when I am 2 miles away.

 

To some extent, MIMO relies upon Rayleigh fading. With a highly proximate, direct line of sight to the serving sector antennas, a MIMO connection may not be possible. With current 2x2 downlink MIMO devices, lack of MIMO connection halves potential data rates.

 

Also....does a higher noise ratio = better connection/speed?

 

Nope, just the opposite -- the higher the signal to noise ratio, the higher the potential data rates.

 

AJ

[gr8nuguy]

To some extent, MIMO relies upon Rayleigh fading. With a highly proximate, direct line of sight to the serving sector antennas, a MIMO connection may not be possible. With current 2x2 downlink MIMO devices, lack of MIMO connection halves potential data rates.

 

 

 

Nope, just the opposite -- the higher the signal to noise ratio, the higher the potential data rates.

 

AJ

I had this at my work tonight, great LTE speeds

[koiulpoi]

To some extent, MIMO relies upon Rayleigh fading. With a highly proximate, direct line of sight to the serving sector antennas, a MIMO connection may not be possible. With current 2x2 downlink MIMO devices, lack of MIMO connection halves potential data rates.

 

 

 

Nope, just the opposite -- the higher the signal to noise ratio, the higher the potential data rates.

 

AJ

I have no idea what you just said. I have two questions for you.

1) Can you explain that, or at least give a decent link to information as to where I can start to learn?

2) Will you marry me?

[WiWavelength]

I have no idea what you just said.

 

If multipath makes sense, then just know that Rayleigh fading is the result of multipath. It is the reason why signal strength can vary by 5-10 dB over just a few feet, even inches in some cases. And MIMO relies on multipath to some extent to produce a strong signal at one antenna, a weak signal at the other antenna, and vice versa.

 

AJ

[koiulpoi]

If multipath makes sense, then just know that Rayleigh fading is the result of multipath. It is the reason why signal strength can vary by 5-10 dB over just a few feet, even inches in some cases. And MIMO relies on multipath to some extent to produce a strong signal at one antenna, a weak signal at the other antenna, and vice versa.

 

AJ

Yeesh... I knew I should have paid more attention to those ham radio classes. All I remember now is how annoying Morse Code is. And that we figured blasting 5W of power next to our heads was no problem for a handheld radio.

 

Thanks for answering my question, as always.

[xenadu]

MIMO gives you space-divison multiplexing... there is nothing special about radio waves vs light you can see - they are both electromagnetic energy. Antennas are just eyes that see in a different part of the spectrum. Things like walls "look" like smoky glass at radio wavelengths. Stuff like aluminum can be a good lens for infrared. Once you wrap your brain around this idea, it all makes sense. Why are 2.4-2.5Ghz signals absorbed by the atmosphere so much? Because the water in the air makes it "look" like eternal fog at that frequency... so duh, you can't see as far on a foggy day. Same deal for WiMax/WiFi.... the antennas can't "see" as far due to the "fog", except that fog never clears up.

 

 

It's a very, very rough analogy but think of MIMO as binocular vision; it allows the tower to "see" where different transmitters are in space. That's the multiple input part of MIMO. Even though two devices are transmitting on the same frequency to the same cell on the same tower at the same time, the tower can separate the signals because it knows where each one is in physical space. Without it, the tower couldn't separate who was who (like trying to play dodge-ball with one eye closed)

 

In the opposite direction, the most advance stuff actually shapes/steers the transmission beam to direct the signal only toward the desired receiver, leaving it free to transmit a completely different signal to a different receiver, as long as that other receiver is located in a different place in space; that's the multiple output part of MIMO. By having two or more antennas transmitting, you can transmit a slightly out of phase or adjusted signal from other antennas, causing the interference to cancel the signal out in some directions but reinforce it in others. You see the same technology in concert line array systems where the long column of speakers are slightly adjusted in timing/phase to "steer" the sound in one direction or another.

 

The phones, by having multiple receiving antennas do the same "binocular" vision thing to "see" the tower more clearly. The multipath thing WiWavelength is talking about is where the signal bounces around the environment, causing echos/reflections. Normally the phone wouldn't be able to tell if the reflection is part of a later signal or just junk reflected from an earlier one. By being able to sort out where the signal is coming from, it can subtract any stray reflections out.

 

 

WiWavelength - please correct me if I've screwed any of this up.

[aparish21]

Running EVO LTE with CM 10 so I can't get the normal stats from dialer but I pulled this app, Network Info,

 

https://play.google.....android.telnet which is showing an reception stat of -85 dbm (ASU:99)

 

 

 

 

while the status section under phone settings is showing reception of -105 (ASU:97) and shows mobile network type as LTE:13.

 

 

 

Just wondering if this App is really seeing LTE signal because the phone gives me full bars when it says connected to LTE but it drops to 1-2 of 4 when I turn off LTE and go to CDMA/EVDO and the app and the phone then show ranges of -79 to -88 while connected to EVDO A,

 

what do you guys think.... sorry no screenshots

[anevojk]

I'm pretty sure the same goes for iPhones: *3001#12345#*

 

I can confirm this works on my iPhone 5. Unfortunately no LTE in San Diego yet.

Edited October 4, 2012 by anevojk

[smac7]

is there anyway to reduce the threshold for connecting to lte? i get -112 here and i wouldn't mind trying to see what speed i get. Could it be slower than the 100-200 mbps i get now (on a good day)?

[WiWavelength]

Could it be slower than the 100-200 mbps i get now (on a good day)?

 

I guarantee that it will be slower than 100-200 Mbps on any day, good or bad.

 

AJ

[Craig]

Question for ya. When I go into the ##3282# menu and set my SGS3 to LTE only mode, what do the bars represent then? There is no CDMA/EvDO signal at that point, yet I get signal bars in the notification area. The site location is listed as unknown in RF Tracker when connected in LTE only mode, so I know it's not getting any info from an EvDO signal.

[S4GRU]

Question for ya. When I go into the ##3282# menu and set my SGS3 to LTE only mode' date=' what do the bars represent then? There is no CDMA/EvDO signal at that point, yet I get signal bars in the notification area. The site location is listed as unknown in RF Tracker when connected in LTE only mode, so I know it's not getting any info from an EvDO signal.[/quote']

 

We have had people report when they go into LTE only mode it appears to show LTE signal strength.

 

Robert via Samsung Note II using Forum Runner

[Craig]

My signal strength was about -113dB (via the LTE engineering menu), yet it showed full RSSI bars. I'm not sure it's calibrated correctly if that is the case. Not that it really matters, just more a curiosity.

[Burgertime]

Getting around - 93 here in Charlotte

 

Sent from my EVO using Tapatalk 2

 

 

[Moropo]

For the S3, when connected to LTE if you go to Settings->About->Status is that still measuring the signal of 1x or LTE?

[boomerbubba]

For the S3, when connected to LTE if you go to Settings->About->Status is that still measuring the signal of 1x or LTE?

 

It's shows the 1x signal. The only place to see the LTE signal strength is the LTE Engineering screen. See instructions at the top of this thread.

[DaQue]

Note 2 detail the same as the S3? Not that I will need for a few months.

[Moropo]

It's shows the 1x signal. The only place to see the LTE signal strength is the LTE Engineering screen. See instructions at the top of this thread.

 

Yes I know about it. Reason I asked is because I remembered Robert saying that one phone actually displayed the LTE signal levels in the About-Status menu and so I asked to see if it was the S3. However, I just found Robert's post and it is actually the EVO LTE that does it.

[jefbal99]

Galaxy Note 2 is the same as the Galaxy S3 method to access the debug menus.