Carrier aggregation (CA) in LTE


Background 

The demand for higher peak and higher average throughput in mobile devices has always existed. Services like YouTube, video calls and live streaming require high data speeds. In order to meet the current throughput demands and increase LTE bandwidth, a very promising feature has been introduced in LTE Advanced (3GPP rel 10 onwards)  known as carrier aggregation.

Introduction


  • CA is a cost effective way for operators to utilize their fragmented spectrum spreaded across different or same bands in order to improve end user experience
  • The basic idea of carrier aggregation is to increase user throughput by sending data simultaneously over two carriers
  • Regular cell known as primary cell (PCell) is combined/aggregated with logical cell (known as Secondary cell or SCell), serving the same cell site. Each aggregated carrier is known as component carrier, CC
    • Example: Operator A has a LTE network deployed using its 5MHz spectrum in band 3. Maximum throughput available in any cell with 2x2 MIMO is 36.2 Mbps. Operator A also has 5 MHz unused spectrum in band 5. Now the throughput can be doubled by combining both 5 MHz spectrums from two different bands using carrier aggregation 
  • The PCell is the main carrier with which UE will communicate i.e. RRC/NAS messages exchange, measurement, RACH etc. PCell always remains active in RRC Connected mode while SCell is activated/deactivated whenever required e.g. when high throughput is required
  • PCell has PDCCH in downlink and PUCCH in uplink but SCell has only PDCCH in downlink
  • 'RRC Connection Reconfiguration' procedure is used to add/remove SCell
  • As per 3GPP standardization, maximum of five component carrier can be aggregated with each component carrier having bandwidth of 1.4, 3, 5, 10, 15 or 20 MHz. The maximum possible aggregated bandwidth can be 100 MHz (20 x 5)




  • CA aggregation is available for both FDD and TDD and the feature is backward compatible which means that the users from rel8 and rel9 can connect to CA capable site by utilizing part of total bandwidth
  • The commercial deployment of carrier aggregation has already started since 2013
Three are three types of carrier aggregation

Intra-Band Contiguous CA
When two or more component carriers belong to same frequency band and they are contiguous. There must be spacing of 300 khz x N between two contiguous component carriers (N is integer). This is the simplest form of CA aggregation from operators perspective


Intra-Band Non-Contiguous CA
When two or more component carriers belong to same frequency band but they are separated by one or more frequency gaps


Inter-Band Non-Contiguous CA
When two or more component carriers belong to different frequency bands.
This type of CA is implemented by operators who own fragmented spectrum





23 comments:

  1. Thanks for sharing here
    I am very happy to read your review
    I hope you give a useful topic for everyone
    Vimax Asli - Thanks this has been my natural looking,
    I will always wait for your latest article - Vimax Asli

    Harga Vimax Asli
    Harga Vimax Asli 2015
    Jual Vimax Asli Canada

    Contoh Vimax Asli
    Cara Kerja Vimax Asli
    Jual Vimax Asli Canada

    ReplyDelete
  2. Hi, can you share something on LTE kpi analysis??

    ReplyDelete
  3. نجار ابواب بالرياض نجار ابواب بالرياض
    تركيب ستائر بالرياض افضل شركة تركيب ستائر بالرياض
    تنظيف مكيفات بالرياض شركة غسيل مكيفات بالرياض
    شركة تنظيف افران الغاز بالرياض تنظيف افران بالرياض

    ReplyDelete
  4. Nice post. I learn something more challenging on different blogs everyday. It will always be stimulating to read content from other writers and practice a little something from their store. I’d prefer to use some with the content on my blog whether you don’t mind. Natually I’ll give you a link on your web blog. Thanks for sharing.

    Home Land
    Homegrounds.webflow.io

    ReplyDelete
  5. Aw, this was a really nice post. In idea I would like to put in writing like this additionally – taking time and actual effort to make a very good article… but what can I say… I procrastinate alot and by no means seem to get something done.

    Spyropress.com
    Information

    ReplyDelete
  6. Hello! I just would like to give a huge thumbs up for the great info you have here on this post. I will be coming back to your blog for more soon.

    Click Here
    Visit Web

    ReplyDelete
  7. There are some interesting points in time in this article but I don’t know if I see all of them center to heart. There is some validity but I will take hold opinion until I look into it further. Good article, thanks and we want more! Added to FeedBurner as well

    Visit Web
    Studiopress.community
    Information

    ReplyDelete
  8. I was very pleased to find this web-site. I wanted to thanks for your time for this wonderful read!! I definitely enjoying every little bit of it and I have you bookmarked to check out new stuff you blog post.

    Click Here
    Visit Web
    Artstation.com

    ReplyDelete
  9. You should take part in a contest for one of the best blogs on the web. I will recommend this site!

    Visit Web
    Hwwc.mg
    Information

    ReplyDelete
  10. There are certainly a lot of details like that to take into consideration. That is a great point to bring up. I offer the thoughts above as general inspiration but clearly there are questions like the one you bring up where the most important thing will be working in honest good faith. I don?t know if best practices have emerged around things like that, but I am sure that your job is clearly identified as a fair game. Both boys and girls feel the impact of just a moment’s pleasure, for the rest of their lives.

    Stylist-profi.ru
    Information
    Click Here
    Visit Web

    ReplyDelete
  11. .......it's important to keep a strict eye on your stocked pet food. Since you will be with your pet almost all the time, you might be tempted to feed him extra just to keep him happy.
    poodle puppies for adoption
    poodle puppies for sale
    https://shihtzubliss.blogspot.com/2021/03/why-choose-us-toy-poodle-for-sale-to.html

    ReplyDelete
  12. Thanks for commenting! I'm sure you would be more than capable to do this swap.
    It's a swap where you can be as creative as you want, or just do something simple, and I am expecting more Good content writing from you. I have also something to share here.

    Glock 17 for sale cheap online without License overnight delivery (glockgunstore.com)

    listateacuppuppies for sale online

    how to buy weed online

    teacup yorkie for sale

    echten führerschein kaufen

    listateacuppuppies for sale online

    have also something to share here.

    ReplyDelete
  13. I know your expertise on this. I must say we should have an online discussion on this. Writing only comments will close the discussion straight away! And will restrict the benefits from this information.
    thc lollipops uk

    ReplyDelete
  14. Very nice post, If you learn how to take a hit, you will be able to absorb the impact and protect yourself from any injuries. Do My College Homework

    ReplyDelete
  15. I'm impressed, I must say. Very rarely do I come across a blog thats both informative and entertaining, and let me tell you, you ve hit the nail on the head. Your blog is important.. Teknobilgi

    ReplyDelete
  16. After study a few of the blog posts on your website now, and I truly like your way of blogging. I bookmarked it to my bookmark website list and will be checking back soon. Pls check out my web site as well and let me know what you think.

    Furaffinity.net
    Information
    Click Here
    Visit Web

    ReplyDelete
  17. Customized baskets for your loved ones! Handing over throughout karachi! Add a customized cake, teddy undergo, sweets, first rate leather wallets, leather-based belts, online gift delivery in pakistan or a balloon bunch. We concentrate on nearby present basket shipping to karachi, pakistan, and heaps of towns all over the global.

    ReplyDelete
  18. We focus on local gift basket delivery to several cities throughout the world, including Karachi, Pakistan. baskets made to order for your loved ones. Shoplectic

    ReplyDelete