Colton123

Sony has already done it.

Which Sony device supports this? 

No handset has implemented 4x4 downlink MIMO.  That requires four discrete downlink antennas.  Wake me when it happens.

 

AJ

Yes, probably to many antennas to fit in a smartphone. But what about for a home router that is always plugged into power. You would think that would have enough room. Kind of like Verizon with their Cantenna solution. Does nothing like that exist for Sprint? I though Sprint was doing Broadband to the home in some markets using LTE? 

So it's like the Nexus 5X. Baseband support for 3xCA but no antennas for it?

I believe you can still do carrier aggregation with just 2 antennas (2x2 MIMO), but I am sure AJ will clarify.

What I am talking about is 4x4 on a single carrier which it seems that Samsung failed to implement though the basband qualcomm modem supports it. 

So it looks like the Samsung S7 is about to come out, and it has the new Qualcomm Snapdragon 820 processor with X12 LTE. Looks like this modem supports Up to 4x4 MIMO on one carrier! Based on previous threads most people said there is no a 4x4 MIMO capable UE device, so I guess that has now changed? 

Will Sprint allow 4x4 on a single carrier? Does Spring support 256-QAM in the down-link? Or what about 64-QAM in the uplink? 

This is a good comparison chart of the diffrrent Qualcom modems: 

https://www.qualcomm.com/products/snapdragon/modems

Is this a game changer?

How many 20Mhz wide Band 41 channels does sprint have deployed in most markets? 

There is no such thing as "single CA."  That would be 1x CA, which is not CA.

 

AJ

Yep, that is what I meant sorry for throwing the CA in there  

But that PR numbers are based on 110Mbps per 20Mhz right, which is config 2 not 1. So the PR numbers are right if Sprint were using config 2 which they are not. 

This is what Sprint planned in 2014 for 2015 and beyond:

3x channel CA at 2x2 Mimo 330 megabits down

3x CA at 4x4 MIMO 660 megabits down

3x CA at 8x8 MIMO 1320 aka gigabits

 

The so called magical 8T8R 2.5gz anntenas that magentans love to mock are network future proof and they are actually for when 8x8 MIMO becomes available years down the road.

http://www.lightreading.com/mobile/4g-lte/sprint-promises-180mbit-s-peaks-in-2015/d/d-id/709518

Based on those numbers, its looks like the are quoting about 110Mbps download bases on a single CA 2x2 right? I guess these slides are based on using LTE TTD Configration 2 which has a max of 112.5Mbps which is darn close to 110Mbps quoted right?

As mentioned, Sprint uses configuration 1 right? 

It is number 1. MIMO reuses spectrum and carrier aggregation adds a different block of spectrum. A device can be 4x4 MIMO and CA two 20Mhz blocks for a total of 8 spacial streams but that is 2+ years away only in labs testing now.

Thanks! What about the case with carrier aggregation of two separate 20Mhz blocks, and 2x2 on each block for a total of 4 streams? Are there sprint devices that can do this today? What LTE UE Category are those kind of devices? 

I assume there are no Cat 5 devices on Sprint at this time?

Aren't the latest smartphones like the Iphone 6s and Samsung S6 CAT 6 devices? Looking at the LTE UE chart, it shows that CAT 6 devices can had 2 or 4 Maximum number of supported layers for spatial multiplexing in DL. Do all the more advanced smartphones just have 2 and not 4?

What about something like the Note 5 which is a CAT 9 device? 

Anyone know what tools we can do this with? 

We need not overcomplicate this.  For MIMO, forget about uplink.  Uplink MIMO may not happen for a good while.

 

So, it is downlink MIMO.  And 2x2 downlink MIMO means two separate downlink Tx antennas at the base station and two separate downlink Rx antennas at the handset.

 

Simple as that.

 

AJ

AJ, thank you so much for explaining this. I now understand what they mean!

So, CAT 5 devices have 4x4 MIMO right? So those devices should be able to double the downlink speed right? Hence why CAT5 UE devices are rated at 300Mbps (for LTE FDD), but CAT 4 are only rated for 150.8Mbps since they only support 2x2.  

Is this double the download speed done by:

1. Taking a single 20Mhz wide TTD-LTE channel, and sending 4 streams of it to the end user.

2. Taking two separate 20Mhz wide TTD-LTE channels, doing carrier aggregation for a total of 40Mhz, and sending 2 streams of the primary 20Mhz wide channel, and 2 streams of the secondary 20Mhz wide channel? 

Because the UE is 2x2, 4x2, or 4x4 on the download side of the UE. People don't talk about the 1x? upload side because no one really cares about upload that much. If people cared about upload they would say "my 2x2 SU-MIMO down and 1x1 SU-MIMO up device sucks on the upload. It is always half my download speeds on an empty site."

But isn't the A X B of the UE in MIMO, on the A is the number of receive antennas, and the B the number or send antennas? Does a 2x2 UE device really have 2 antennas used for uploading data back to the cell tower? 

Understood. 

Why are they calling UE devices 2x2, 4x2, or 4x4 then if at max only 1 stream can be used in the upload side? So really these devices are 2x1, 2x1, or 4x1 right? 

Yes, I too think I was a little confused.

So, just to confirm, for tower MIMO Sprint is using 8x8 on the tower right?

For the UE, what is confusing me is you say most of the UE devices out there are 2x2 MIMO today. Based on what I have seen however they can only use 1 stream on the upload side, so really are these devices 2x1 devices? Two streams for download and 1 stream for upload? 

No. 

 

4x2 is a eNB enhancement. To double speeds, 4x4 MIMO must be utilized on both the eNB and UE.  Devices available today are only capable of 2x2 UE. 

 

4x4 MIMO as in 4 Tx streams from eNB going to UE and 4 Tx streams going back to eNB from UE. 

 I was not understanding how that makes any sense, but now I read that the original OP was talking about the max upload speeds, and I was talking about download speeds. 

So just to confirm, the best UE devices today are 4X2 right? Which UE category device is that?

A 4x2 UE device can obtain double the download speeds of a 2x2 UE device, but has exactly the same upload speed right?

So using one 20Mhz wide TTD-LTE channel, what is the max download speed a 4x2 UE device can obtain based on sprint's 1 configuration? I assume its 164.6Mbps? That is 82.3Mbps times 2. 

I know there is carrier aggregation so that confuses things even more. But lets assume Sprint only have one 20Mhz wide TTD-LTE channel. 

Category 3,4,6,9, 10

 

4x2 Mimo is eNB antenna configuration. Instead of two Tx streams aimed at the UE, there are 4 which improves SINR, edge of cell connectivity, and stability of speeds at all signal levels.

 

The antennas and radios are 8T8R meaning there's 8 Tx/Rx antennas active to broadcast the connection. For speeds Look at the chart. It lists the theoretical speeds for every LTE MHz configuration.

I did look at the chart, but what is not clear to me is the chart showing 1 stream, 2, or 4.

I read this article, http://www.ijitee.org/attachments/File/v3i12/L16590531214.pdf. Using 2 streams it get the 82Mbps number you mentioned, but the calculation shows 2 streams. I assume this means a 2x1 UE device? http://www.ijitee.org/attachments/File/v3i12/L16590531214.pdf

So with a 4x2 UE device can I double the number you have in your chart? 

So what about Huawei? I know Sprint is supposed to be ripping them out due to security concerns, but someone told me that Huawei was able to upgrade all the old Clearwire WiMAX base stations to LTE. I do not beleive its 8x8 configuration, but I could be wrong. Where does Huawei with LTE fit in Sprints network since its not on the map above. 

So which category is the current 2x2 devices? And which category is 4x2 devices?

Is the 82.3Mbps download rate for configuration 1 with 20Mhz channel size for a device with just 2x2 or a device with 1x1? 

Very confused is the tower is 8x8 but the UE's are only 2x2 or 4x2 today, then what are max speeds obtainable. Assume only connected to 1 20Mhz Band 41 TDD channel.

So are those rates assuming 2x2 MIMO, or which Category device? Sprints base stations are 8x8, so what is the max speeds one could get? 

So Sprint uses Configuration 1 I assume? 

Where can I find The Wall? 

Some devices, like the Note 5 for example, are Category 9 devices. Others, like newest iPhone are Cat 6. I realize its all about what Sprint has configured as to what is the max speed obtainable, but I am just asking in general which LTE Band 41 devices are rated for the most speed ie higher LTE Cat. 

Thanks for the quick reply. Tech wise are they all the same, or what makes you say Nokia?

In the map the south looks to be Nokia. Your pictures mention Ericsson/Nokia. Does Sprint use just Nokia for LTE Band 41, or both of them in the south? 

How do you tell which LTE UE Category a device falls into? Most of the specs on the Sprint website and/or manufacturer website does not say which UE Category a device falls under.

What is the best data only device that Sprint sells? Which has the highest UE rating? 

Which LTE Band 41 base stations is Sprint using? I have read they use multiple vendors, but I am not sure who the vendors are nor which they use in what market. Is one vendor's base station better than the others? 

Which spectrum analyzers do you recommend that can pickup LTE Band 41 that sprint uses? Goal here is to see in a certian market which LTE channels Sprint is using, and how large the channel sizes are. Also interested to see if any of the educational entities are actually using their EBS licenses, or if Sprint is using them.

This seems like a valid solution as it support up to 2700Mhz. http://shop.nutsaboutnets.com/products/model-6gcombo 

Is there anyway to do this on an Android phone that has Band 41 built in already?  

 

 

lilotimz, can I asked where you got these orange graphs from, and if there are more of them somewhere? I would like see see the different up and download rates for TDD.