Carrier Aggregation in LTE - Theory + Log analysis

This video starts with theory of Carrier Aggregation and then moves to UE log analysis for CA. It also discusses, cross carrier scheduling and impact of CA on various layers of LTE protocol stack.

[@oomkara]

I must say very crisp and to the point ,easy to understand.Probably one of the best info piece for CA. Great job.Thanks

[@sathyaprasadnayak9149]

Very good video to understand CA !! Carrier Aggregation Basics Explained in very simple way. The best part is the tutorial is very practical as theory has been explained with 3GPP IEs. Generally this co-relation is the toughest part

[@ibrahimkamhieh3600]

Very excellent explanation. Appreciated

[@talkinghat88]

Like the way you explain the processes. Very logical and practical. Thanks

[@wottowutzke]

Very nice, important and GOOD BACKGROUND,,, I´m learning a lot with this video... Thanks a lot

[@mysterious_miracle]

Such a wonderful tutorial, I wish you made one for MIMO as well

[@butchsapida]

Excellent explanation. clear anddirect to the point. thank you for sharing

[@pritiranjanrout273]

I have gone through many of your LTE sessions. All are really wonderful. Are you also planning to share similar kind of NR Sessions as well.

[@gauravchughpisces]

Hello, great work "D"ude :) All the topics in your channel are explained well and in very simplified manner. Keep up the good work.Looking forward for more.

[@LTEVideoTutorials]

Thanks Gaurav!!

[@mohammadfayaz9106]

Spot on. Complete knowledge is here.

[@dineshdhiman8534]

Superb work bro thanks a lot for this video deep understanding of CA

[@Mahimammu]

Very Good Video for CA. Thank you very much Sir

[@luisalfonzogonzalez2265]

AMAZING!!!!! Thanks a lot

[@gaurishkadam3839]

Minor Correction @7:01 CA_25A_41C - is one carrier from band 25 and two contiguous carriers from band 41

[@vaibhavdudhe8567]

Nice information Please give video on Throughput failure analysis from device side Or CA throughput debugging

[@infomatrix7149]

videos on lte-A cellselection+handovers with log analysis,and lot more...thanks a ton.

[@simranrajgupta8462]

There are test case scenarios, in which My Secondary cell (y) becomes primary cell (x), and Primary(x) becomes secondary cell(y) and then the current secondary cell gets removed after data transmission completed. How we can see that in log?

[@phanpeace2757]

Tks a lot. So in supportedBandcombination, such as 1A-3A in your video, please more details about DL and UL, as I saw band 1 support DL class A, and band 3 support both class A in UL and DL --> so in this example: support CA 1A-3A in DL . How about UL in band 3 and band 1 ?

[@pandarivetoori8615]

Okay... Same thing came in my mind if all spec, categories same n having NGBR/GBR... but anyway I'll watch it..... Thanks

[@saxenarohit59]

please explain where we can see bit111 and bit 112 in featuregroupindrel in the trace

[@riyasingh1905]

Thanks for this good detailed video.

[@rajiv2109]

Excellent explanation....great work....

[@saxenarohit59]

in bandwidth combination set , how to calculate maximum aggregated bandwidth. Please explain sir

[@basherpvpv3907]

Nice video ..thank you ..could you please explain Load balancing in LTE..

[@saxenarohit59]

For bandwidth combination set 0 , UE does not send IE....What does "IE" refers to? Also is this band combination set fixed for 0,1 and 2 that is 8 ,4 and 2 or it is just an arbitrary example

[@ibrahimkamhieh3600]

DO you have videos for 4G planning & optimization?

[@feratube10]

Excellent video, I like the way you explain this topic, very good, thanks a lot. I am wondering about the scenario to test CA, could you please let me know one or two ways to test/verify CA ? what tools are needed ? what can I do to create enough traffic to force the UE to do CA ? In advance thanks again and keep up the good job your are doing.

[@LTEVideoTutorials]

Thanks for such a positive feedback. It really motivates me. First condition for CA is that network should have configured it. So, first of all search for a CA area. For this searching you need CA capable mobile. Mostly, operators configure CA in city centers or highly populated areas. Data threshold has nothing to do with CA allocated. Only thing needed is that secondary cell should meet the measurement criterion. If you have a active data flow and second cell is added to the UE, eNodeB will activate the secondary cell to make data completion quicker. You can check activation of secondary cell either by using the suitable AT command. I do not remember the command at this moment. Or you can analyse RRC logs to confirm activation of secondary cell. Hope this will help.

[@nicolaeprisacaru5759]

Very good video. Thank you

[@pinakiroy3878]

good explanation. Please keep more videos coming :)

[@LTEVideoTutorials]

Thanks!

[@umeshpawar7469]

Very nice explanation.. with clear understanding... Can you upload presentation for LTE-MIMO technology with UE log snippets... ? can you let me apart from support of rel-10 and onward release, is any limitations for using CA ?? please let me know how CA relates to Dual/Three carrier cell in HSPA ???

[@LTEVideoTutorials]

Thanks Umesh for feedback! 1) Okay, I will try to cover MIMO with log analysis in coming days. 2) As such there is no limitation, but rel-10 is not the only thing needed. UE's physical layer should also support carrier aggregation. So, list of UE's capabilities sent by UE in UE capability message play a major role for allocation of CA. That is why, I have discussed this message in detail in this video. 3) It is very difficult to do one on one comparison, but they are similar as both of them allow UE to get data on a wider channel bandwidth.

[@saxenarohit59]

in your slide, you said UE wil add cell 199 as secondary cell, why it is so?

[@srikantamahanta82]

very much helpful

[@prudhvikassetty4400]

How will I know it’s “IntraBand Non-contiguous” from Log?? CA_3A_3A?

[@mysterious_miracle]

Excellente

[@indramani8888]

what would be the meaning of 7A ???

[@infomatrix7149]

time 12m:57, Why device select phyCellid 199 as secoundery cell,why not phycellID 130?

[@devikaghate2473]

Could you please share the slides of these ppt

[@PARKATAMURGA]

post more videos of lte please :) great work!!

[@umeshpawar7469]

hi.. expert.. where have you been.. i was looking for this video again.. but couldn't find it.. when i tried to search it gave an error..

[@LTEVideoTutorials]

Hi Umesh..by mistake youtube suspended my channel in feb..I submitted a request to reinstate it..they admitted that by mistake they suspended my channel and unsuspended it today. It was a very bad experience for me too..rather it was a nightmare for me..I can understand what subscribers of this channel would have gone through ..but now everything is fine..I am happy :)

[@kishoreg570]

Hi sir nice video, we are seeing CA is not reported for one the network in US.we need your inputs.

[@shubhankardutta9303]

@LTE Video Tutorials would you like to suggest some good LTE books, which could explain the concepts and theory from scratch

[@LTEVideoTutorials]

Actually no single book will tell you all. I like “Theory to practice” for basics. Don’t remember the exact name. But for latest features such as CA, MIMO internet is the best resource.

[@pandarivetoori8615]

It's really nice making off it rather reading hours together.... Actually I'm RF DT engineer but I'm very intended to know about this protocol stack.... Well don't mind I have one doubt that if there is a 100mb of data in a pipe line we have 100 users now each user get how much about of data..?? Please tell me answer... Thanks for making clips..

[@LTEVideoTutorials]

Firstly, thanks for your feedback. It really matters to me! It is not possible to answer this question by any means. As there are many factors affecting data rate for a given user so data rate for each user will vary. Few of these factors are UE capability and Radio conditions. Theoretically, if all factors are same, available bandwidth will be equally divided among all UEs. MAC layer of eNodeB dynamically allocates resources to each UE based on these varying factors . Please refer to my video on data rate calculation. This video will make things crystal clear. Happy watching 😀

[@mehtatours3165]

There is limitation on number of UEs scheduled per TTI (like 4,6,8,16). Suppose 8 UE per TTI is configured in enodeB. So eNodeB will allocated all the resources among 8 UEs only. Now your next question is how eNodeB decides to allocate how much resources to all UEs. That actually depends on scheduler algorithm. If eNodeB is running on RoundRobin Scheduler then all 8 users will get equal resources, which is not the case generally. So eNodeB manages quality of service and uses different types of QoS scheduler mechanism that calculates priority for all UEs based on Radio conditions and data in buffer as described by Pandari in Comments. Further those resources are divided among 8 users based on priority. In next tti further 8 users can be selected based on priority.

[@advanceddesignsystemadsrfi449]

what is the coding language used to code 12:56 please some once respond

[@nouhakhelifi9910]

Thank you for this brief explanation!Is CA is used in LTE or LTEAdvanced?If it is used for both ,what the difference between CA IN LTE and CA in LTEADVANCED?Thanks in advance

[@LTEVideoTutorials]

nouha khelii CA is used in LTE advanced.

[@anandvishwakarmaanand8463]

whhich layer taking care for S-cell addition or deletion( RRC or MAC)?

[@AK_Allrounder15]

Mac

[@nevskynew2272]

Hi, Your videos are very helpful and very real time experience. I have a question regarding the Bandwidth Combination Set. For CA_1A_8A, why is it not possible for both bands to have combinations 1.4MHz & 1.4MHz, 3MHz & 3MHz? Could you please explain. In simple, why not other combinations possible between these 2 bands BW? I did understand the part "A" refers to RB's less than 100. So in that case, why not Band 1's 3MHz and Band 8's 3MHz.

[@nevskynew2272]

I think I understood after watching it many times. Is it because of 3GPP standards " Table 5.6A 1-2 "from 36.101". I also read the below line in a CA document " For practical purposes, 3GPP limits the number of inter-band combinations defined to those required by operators".

[@LTEVideoTutorials]

Hi Nevsky, thanks for watching the video!! Even, I do not know on basis these combinations are made. But all the possible combinations of bandwidth are defined in the 3GPP specification. You can go to 36.101 and see all kind of combinations such as band combinations, bandwidth combinations etc. for CA. I think as CA is a physical layer concept, so to limit complexities at Physical layer 3GPP has limited the possible combinations. Your research also says the same. But it is nice to see such interesting question. Keep coming!!

[@knag1224]

what does this ca combination define here? CA_3A { bandEUTRA-r10 3, bandParametersUL-r10 { { ca-BandwidthClassUL-r10 a } }, bandParametersDL-r10 { { ca-BandwidthClassDL-r10 a, supportedMIMO-CapabilityDL-r10 twoLayers } } } },

[@dineshd7687]

Intra band contiguous

[@knag1224]

@@dineshd7687 but class A signifies that CA_3A. But there is no single frequency ca he also tells in video that CA_25A will not be mentioned since ca is not supported with single carrier

[@Rkmaniak]

please upload videos on IMS - architecture, registration and call flows

[@LTEVideoTutorials]

Yes, currently I am working on VOLTE. Please wait for some time.

[@debarajsahoo6700]

Hello Sir Very nice explanation on CA in simple ways to understand. How can we know UE 4*4 or 2*2 MIMO enabled or disabled from the message from UE capability information or UE capability enquiry that enodeB received.

[@chabaneelhocine5698]

thanks a lot man

[@thampijeeva-rupan994]

CA_25A_41C: correction instead of Band 1, it should be 25. Correct?

[@LTEVideoTutorials]

Can you please tell timestamp from the video? Then I will check.

[@famStein542]

7:06 CA_25A_41C band25?

[@zeeshangul7090]

Hello, Is it right that we shouldn't take the secondary carrier component's throughput on the Physical layer, rather it should be taken from PDCP layer. (For measurement) Please explain

[@LTEVideoTutorials]

Hi Zeeshan, I did not get your question fully. What is your opinion? Why shouldn't we take throughput from Physical layer and why should be take it from PDCP layer? Please elaborate.

[@zeeshangul7090]

Actually, I am trying to view my TDD 2nd carrier TP, on tems investigation. And I have seen a huge difference b/w PUSH TP and PDCP TP. Normally we take the Phy layer TP, and there is almost no difference b/w the two layesr's. but as I come to 2nd carrier, it shows bugged kind of values on Phy layer

[@ManishSaini74]

Hi Sir, Can You share this presentation with me for documentation. Thanks in advance.

[@LTEVideoTutorials]

It is not a PPT. I have made this video using Camtasia tool.

[@butchsapida]

Excellent explanation. clear anddirect to the point. thank you for sharing