DL 4x4MIMO is not working

[hamody2005]

Dear Expert,



4x4 MIMO is enabled in HW eNB and CFG parameter and licenses are ok, but KPI related to Rank3 & Rank4 shows no PRB are assigned to them.

Could you advise?

[DANORM]

which frequency?

[hamody2005]

it's on Band28

and BW is 10M

[punto]

Is cabling on antenna correct, no crossed feeders ?

[DANORM]

most probably UE does not support of 4T4R for that band


it's on Band28

and BW is 10M

[hamody2005]

Is cabling on antenna correct, no crossed feeders ?

yes, ok connected

[hamody2005]

most probably UE does not support of 4T4R for that band

UE support 4x4 Samsung Note9

[DANORM]

That does not work for Band28. Its working on other bands.


UE support 4x4 Samsung Note9

[hamody2005]

That does not work for Band28. Its working on other bands.

from capability ifound this for band 28 "messagesupportedMIMO-CapabilityDL-r10 = twoLayers"

Does it means it's only 2x2 or its for CA only.

[subway]

I have not seen a single UE that has 4x4 below band 3. Sub-1GHZ is definitely 2x2, but on the RAN side it is similar. Even the dual or triple-band RRUs (ZTE for example) has 4 RX, but only 2 TX per band on combined ports.

But you can attach the full UE capab here, and we can take a look.

[mounir34]

Hello,
which license have you checked my friend ?


Dear Expert,



4x4 MIMO is enabled in HW eNB and CFG parameter and licenses are ok, but KPI related to Rank3 & Rank4 shows no PRB are assigned to them.

Could you advise?

[hamody2005]

Hello,
which license have you checked my friend ?
All licenses related to 4x4
4x4MIMO, BB Tx/Rx channel, RF Tx/Rx channel

[hamody2005]

I have not seen a single UE that has 4x4 below band 3. Sub-1GHZ is definitely 2x2, but on the RAN side it is similar. Even the dual or triple-band RRUs (ZTE for example) has 4 RX, but only 2 TX per band on combined ports.

But you can attach the full UE capab here, and we can take a look.

Please see attached file, which is for Note9, but from message it's Cat4

[auto_art]

cat 4 only can 2 layers.



UL AND DL PARAMETERS FOR LTE UE CATEGORIES 1 – 5



LTE CATEGORY


PARAMETER
LTE CAT 1
LTE CAT 2
LTE CAT 3
LTE CAT 4
LTE CAT 5


Max number of DL-SCH transport block bits received in a TTI
10 296
51 024
102 048
150 752
302 752


Max number of bits of a DL-SCH block received in a TTI
10 296
51 024
75 376
75 376
151 376


Total number of soft channel bits
250 368
1 237 248
1 237 248
1 827 072
3 667 200


Maximum number of supported layers for spatial multiplexing in DL
1
2
2
2
4


Max number of bits of an UL-SCH transport block received in a TTI
5 160
25 456
51 024
51 024
75 376


Support for 64-QAM in UL
No
No
No
No
Yes

[hamody2005]

cat 4 only can 2 layers.



UL AND DL PARAMETERS FOR LTE UE CATEGORIES 1 – 5



LTE CATEGORY


PARAMETER
LTE CAT 1
LTE CAT 2
LTE CAT 3
LTE CAT 4
LTE CAT 5


Max number of DL-SCH transport block bits received in a TTI
10 296
51 024
102 048
150 752
302 752


Max number of bits of a DL-SCH block received in a TTI
10 296
51 024
75 376
75 376
151 376


Total number of soft channel bits
250 368
1 237 248
1 237 248
1 827 072
3 667 200


Maximum number of supported layers for spatial multiplexing in DL
1
2
2
2
4


Max number of bits of an UL-SCH transport block received in a TTI
5 160
25 456
51 024
51 024
75 376


Support for 64-QAM in UL
No
No
No
No
Yes




Thanks , but from Samsung website Note9 is not cat4 "Faster capability in comparison to any other smartphone without a Cat. 18 modem"

[joaoo]

Perfectly normal, I only know 2 phones in the world that support 4x4 in B28, the Sony Xperia 1 (J9110) and Sony Xperia 1III (XB-BC52).

[DANORM]

Do they support B20 4T4R?


Perfectly normal, I only know 2 phones in the world that support 4x4 in B28, the Sony Xperia 1 (J9110) and Sony Xperia 1III (XB-BC52).

[joaoo]

Yes, they suport B20, B28 and also B8 with 4T4R.

[subway]

This phone does not support 4x4 on band 20 or 28 for sure.

Non the less, the fact the modem is Cat4, that does not mean it cannot have 4 receive chains. It can, but not for MIMO (spatial multiplexing), but for simple diversity combining. The UE category only limits the spatial stream number, not the actual receive chain number. :)

[RF_Blida]

vérifier le type de votre UE s'il prend en charge 4T4R