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khurrambilal01
2019-01-02, 01:00 AM
Hello everyone, Happy new year!

We are having Nokia FL18 SW in our network with F1=20Mhz, F2=10Mhz & F3=5Mhz, 4X4 MIMO is active, 256QAM is active and 3CC CA is active too.

We can't achieve Max throughput beyond 154Mbps in field as well from KPIs. We don't have FTP server and we are using External websites for downloading data plus speedtest.net

We have checked transmission side and sites on FTTH also have same maximum throughput which means that transmission part is clear and issue is either on Radio side or Core/SGW side.

Does anyone has any clue what can be the issue?

We are using Samsung S8 for testing which supports 4x4 MIMO, 256QAM, 3CC. We should be able to achieve atleast 300Mbps with all these features active. Our Core is Huawei. The SIM used for testing has been configured with 1Gbps AMBR on MME side.

tuanlatoind
2019-01-02, 11:38 AM
can you share more details for the field test result?
Like Physical throughput, modulation, rank indicator,... which is affected directly to your application throughput


Reputations for me if you think it helpful

khurrambilal01
2019-01-02, 03:19 PM
Thanks for reply.

We are getting RI = 2 and 3CC active, 64QAM modulation being used, RSRP = -83dBm, SINR = 22, Approx 100 PRBs being assigned and even we have restricted the access to the cell by other UEs to test the throughput in no load scenario but throughput never crosses 154mbps.

The throughput on F1 (20mhz) without CA and with 3CC is almost same with no difference.UE doesn't get more PRBs even though the cell has no load.

We are downloading 10GB files from an external website for testing plus playing 4k youtube video.

slava121
2019-01-02, 04:39 PM
Are you using for testing the Samsung Galaxy S8?

khurrambilal01
2019-01-03, 05:18 AM
Yes we are using Samsung S8 variant having 4x4 MIMO support, 256QAM and 3CC support version for testing.


Are you using for testing the Samsung Galaxy S8?

plannerguy
2019-01-03, 07:15 PM
Hi

Have you verified the UE capability info of from DT logs. Does it support the 3CC bands ?

Rgds
Plannerguy

pathloss
2019-01-04, 03:21 AM
Am I right, that your network has 256QAM enabled, but you don't see it on your Phone (S8)? Might I ask if your testphone is an official testphone like TEMS or NEMO or if it's an OEM device? It might be that 256QAM and Rank3/4 (MIMO 4x4) are not enabled in androids carrier settings.

By the way does your APN have a cap/limit?

khurrambilal01
2019-01-04, 07:37 AM
Hi,

Thanks for the response, We are using Samsung S8 offical for TEMs, It has 256QAM/3CC/4x4 MIMO capability but i can see from the logs that 256QAM works fine with 4x4MIMO as well but throughput doesn't go beyond 150Mbps. I can see in the attach messages that AMBR is 1Gbps, Transmission team says the site is FTTH (1Gbps capacity).


Am I right, that your network has 256QAM enabled, but you don't see it on your Phone (S8)? Might I ask if your testphone is an official testphone like TEMS or NEMO or if it's an OEM device? It might be that 256QAM and Rank3/4 (MIMO 4x4) are not enabled in androids carrier settings.

By the way does your APN have a cap/limit?

khurrambilal01
2019-01-04, 07:39 AM
Yes, We can see 3CC active and working but Tpt never goes beyond 150Mbps.
Hi

Have you verified the UE capability info of from DT logs. Does it support the 3CC bands ?

Rgds
Plannerguy

auto_art
2019-01-04, 08:40 AM
can you do a test for the transport? iperf??. we had a case with our GPon network where each circuit was limited to 200Mbps when that limit was removed it was all went well, if you are able to see transport statistics try to see is the payload is flattening.

I would suggest going step by step to troubleshoot.

djordjebeg
2019-01-09, 08:03 AM
I agree that transport is very important , but in such case, you will not observe constantly 100% PRB usage ( or close to 100%).
have you observed in L3 RB Reconfig. a message used for enodeB to configure Scells? Have you observed that Scells are activated? If yes, what throughput distribution you observed? Maybe there is something in setings of CA. If you can share xml configuration of that enodeB maybe I could check.

bawbag11
2019-01-09, 08:30 AM
Hi,

Could try a simple test for TX limitation but you need 2 users & 2 Ue to test but second Ue (and user) can be regular one.
1. Start download with your test Ue on one sector, let it get to max throughput
2. Get another user who is camping in a different sector of the same eNB to start a FTP download

If the first Ue throughput drops, TX / FTP server / onward internet connection is bad. If it stays steady and user 2 also gets good throughput then TX good.

I would really recommend having special FTP / HTTP server (files stored in RAM not DISK) close to core without leaving the operator for these tests as too many variables to guarantee throughput once you get above 100mbit/s on the wider Internet. Had hassle with same kind of testing many times :(.

Regards

marcengo
2019-04-06, 03:48 AM
Yes, We can see 3CC active and working but Tpt never goes beyond 150Mbps.

Hi, Sir.

I`d suggest a couple things:
1) See how is the BLER across the tests. It shouldnt go above 10%.
2) Check the TBS/MCS allocation to see if they make sense. They should be at very high values for SINR=22dB.
3) Check the reported CQI. It should be in the upper range for the vast majority of the time.
4) Check the reported RI (average). It should be near 4 for the majority of time.
5) Can you test two UEs at the same time? This helps to understand if the limitation is in the air interface or from the eNodeB to the back.
6) Can you test different servers for download? All give the same results?


Can you share a small piece from the logs? Better if covers also attach, and at least a IDLE to CONNECTED transition.