Skip to main content

High-level Architecture Introduction of Mobile Cellular Networks from 2G to 5G


Here is an old tutorial explaining high level mobile network architecture, starting from GSM and then looking at GPRS, UMTS, LTE & 5G. Slides and video below



Related links:

Comments

  1. This is a very nice and easy description of technology evolution.

    Can you please help understand why USSD is not part of the 4G (EPC) and 5G (NGCN)? Will USSD get obsolete as the mobile networks phase out 2G and 3G? Would it not be challenging, considering that mobile banking as an evolving service is highly dependent on USSD? Thanks

    ReplyDelete
    Replies
    1. There is an equivalent feature in LTE called USSI. Unfortunately it's not been implemented by many networks.

      Delete
  2. Thank you Zahid. Why is that so? I am trying to evaluate from a third party perspective, whether investing in new USSD gateways is worth undertaking, or is it at a risk of obsolesce?

    ReplyDelete
    Replies
    1. Depends on which part of the world. Areas where 2G and/or 3G will be around (like Sub-Saharan Africa) will continue using USSD. Western world now uses Apps to do the same things.

      Delete

Post a Comment

Popular posts from this blog

IEEE 802.11be Extremely High Throughput (EHT), a.k.a. Wi-Fi 7

We have been writing about Wi-Fi for a long time, weather it's to do with indoor connectivity , competition with 5G or just a name change to something simpler. When we last wrote about WiFi 6, a.k.a. 802.11ax, we were expecting a quick adoption of the technology in the industry. We are still not there yet.  You know what's strange? None of the new @madebygoogle gadgets from yesterday support Wi-Fi 6. Not the Pixel 5, not the Pixel 4a 5G, not the Nest Audio, and not the new Chromecast. pic.twitter.com/QtJ8iB9FeO — Ry Crist (@rycrist) October 1, 2020 Take for instance the new iPhone 12 supports Wi-Fi 6 in all their models as one would expect but none of the new Google Pixel phones (4a, 4a 5G and 5) support it. In fact none of the new Google devices support it. Which is rather bizarre. While we are still looking forward to Wi-Fi 6 becoming widespread, IEEE has already started working on the successor of 802.11ax, 802.11be - Standard for Information technology--Telecommunicati

CSI-RS vs SRS Beamforming

In an issue of Signals Flash by Signals Research Group (SRG), they talked about 2 different types of MIMO. Quoting from their journal, "CSI-RS versus SRS. Those operators that have tested or made token use of MU-MIMO leverage a flavor of MU-MIMO that is based on CSI-RS. The MU-MIMO network we tested was based on SRS, which makes it far more likely to observe sixteen spatial layers (versus eight)." I reached out to Emil Björnson, Visiting Professor at KTH Royal Institute of Technology and Associate Professor at Linköping University to see if he has explained this in any of his videos. Here is what he said: " I'm not talking about 3GPP terminology in any of my videos. But you can listen to the slides that starts around 12:40 in this video (embedded below) . If you are looking for CSI-RS vs SRS based MU-MIMO, then jump to around 12:40 in this video where you can see CSI-RS being referred to as "grid of beams" and SRS is similar to the other option, which is t