LTE - How to Ensure UEs are allocated 64QAM MCS

[khalids]

Dear Experts, I am having cells with more (80%)QPSK MCS allocation and very few (5%) 64QAM MCS allocations.
What can i do to ensure that more 64QAM MC allocations are given.


Cell Id

DL TB = QPSK(%)
DL TB = 64QAM(%)



2
99.94
0


2
88.42
0.59


1
83.38
5.79



1
81.81
5.86


2
79.98
2.69



What parameters can i check and what can i do for improvements.

All feedback will be most appreciated.

[Shakeel_15]

Hello,

MCS depends on CQI (Channel Quality Index) and CQI depends on SINR.

You first need to check the radio conditions Coverage, SINR etc

Check distribution porpotion or Average CQI.

In short if SINR will improve CQI will Improve, if CQI will improve you will get high MCS.

BR

[agenov]

it doesnt mean you have a problem, could be traffic demand case. there are many things you can check and do, i would suggest you to perform a drive test with cont download and if the results are still the same then based on result analyzes to perform some changes/actions


br
alex


Dear Experts, I am having cells with more (80%)QPSK MCS allocation and very few (5%) 64QAM MCS allocations.
What can i do to ensure that more 64QAM MC allocations are given.


Cell Id
DL TB = QPSK(%)
DL TB = 64QAM(%)


2
99.94
0


2
88.42
0.59


1
83.38
5.79


1
81.81
5.86


2
79.98
2.69



What parameters can i check and what can i do for improvements.

All feedback will be most appreciated.

[plannerguy]

Hi

which Vendor

[techfolkcmr]

With 64QAM enabled what's the maximum speed u achieved. In our case 64QAM in DL is configured but shows 0% utilisation in log files and our vendor is ZTE. Want to know one more thing we have Huawei and Zte in our nw. In Huawei max of 14.4 mbps enabled with 64qam disabled whereas in zte 64qam I configured in downlink with max of 21.1 mbps. In zte areas we are getting H+ symbol and in Huawei we get only H Symbol. I must admit that on average both networks are providing almost same speed. Though 64QAm is configured in ZTE why there is 0% utilisation and is 64qam is the reason for H+ Symbol.Somebody pls explain things.My Query is regarding UMTS.

[khalids]

We use Huawei EnodeB

[kentck86]

We use Huawei EnodeB

Please check if any parameter inconsistency?

[jenriqp]

Hi all,

Check TA and get users distributions because if you have many users far from cell that could be the problem, cell will do low mcs.

[techfolkcmr]

Sorry again for interrupting here. My question is regarding UMTS. In our ZTE network though in drive test around 70% of CQI value are above 26, 64QAM modulation used is only 2%. On contacting vendor, he replies Modulation is allotted based on TBF Size which in turn allotted based on CQI. (i.e) according to his statement CQI >>>> Decides >>> TBF >>>> Decides >>>> Modulation but what we believe is CQI>>>>>>Decides>>>>>Modulation>>>>>Decides>>>>TBF. Could someone pls clarify. It would be great to understand the basic concepts. Thanks in advance.

[jenriqp]

Hi,

I think, your doubts has to be discussed in an independent post. So CQI values are sent by UE periodically to serving cell on uplink (HS-DPCCH). That informs to node B which data rate UE is able to receive at that time. therefore CQI reported corresponds to a TB that can be guaranteed on a type of modulation and HS-PDSCH codes numbers. you should remember UE categories and 3GPP table about this mapping.