Colton123

Which Sony device supports this?

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?

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?

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.

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?

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?

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?

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?

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.

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?