4G/LTE - Basic Procedures





Multi Cell / InterRAT


Everybody who has experience with dealing with field trouble would know that this is never ending story, regardless of whether it is UE side issue or Network side issue.

This means that this technote will never be complete (It means the pages regarding this topic would expand forever as I pickup more experiences and experience more problems). I will be updated forever and you have to revisit this page forever as well -:)


Since this is an huge topic, I split it into multiple pages. Only the first topic (big picture) will be directly described in this page and all other topics are linked as a separate page. Just click on the topics you are interested in.


State Machine Overview


Before you go through the detailed process of each cases, I would recommend you to spend some time on following state diagram and get a big picture of various multi cell scenario. For the detailed steps indicated on this state diagram, I will post separate pages and you can get the pages via the link listed above. In this section, just take a look at these diagram whenever you have chance and let your brain draw the pictures in your mind on its own.


The simplest multi cell cases would be between two LTE cells. We call this kind case as IntraRAT multi cell scenario.



More complicated (probably the most complicated) cases are the multi cell scenario among different technologies (different RATs). The big/high level picture would be as follows.