top button
Flag Notify
    Connect to us
      Facebook Login
      Site Registration Why to Join

Facebook Login
Site Registration

What is the difference in operations of DRX in connected mode and DRX in IDle mode?

+1 vote
866 views
What is the difference in operations of DRX in connected mode and DRX in IDle mode?
posted May 16, 2014 by Nikhil Pandey

Share this question
Facebook Share Button Twitter Share Button Google+ Share Button LinkedIn Share Button Multiple Social Share Button
UE shouldn't remain asleep in idle mode. If any downlink data comes , it should be paged. So UE is given (chosen by itself or configured by eNB) occasion to wake up & receive the message .
In Connected state also , he may remain inactive for some time as there
might not be any data to send & receive but still UE keeps monitoring PDCCH , that consumes battery henceforth ue is configured with C-Drx so he can listen to pdcch Discontinuously so as to save battery power.

1 Answer

+1 vote

In RRC idle mode the UE only needs to wake up every paging period to check if there are incoming paging for the UE (as well as possible modification of system information/ETWS/CMAS transmission). In addition, for mobility purposes the UE needs to perform certain measurements (such as serving cell RSRP, possibly also RSRQ, and neighbour measurements depending on serving cell radio signal strength /quality as well as network configured parameters).

In RRC connected mode, the usage of DRX is somewhat different and opportunistic (if DRX is configured and there is no data to be sent or received, the UE can enter specified inactivity period) in a sense.

If you want to go in more deep. Read below links:

http://lteuniversity.com/get_trained/expert_opinion1/b/prakash/archive/2013/04/17/discontinuous-reception-drx-in-rrc-idle-part-1.aspx

http://allabtlte.blogspot.in/2014/01/all-about-discontinuous-reception-drx.html

http://www.telecomfunda.com/2014/05/discontinuous-reception-drx-in-rrc_idle/

answer May 19, 2014 by Hiteshwar Thakur
Similar Questions
+1 vote

Which messages eNodeB uses to configure connected mode DRX and idle mode DRX for an UE ?

+2 votes

During my study about the measurement and ANR, I have the question. Please help to let me get the proper answer.
[ Condition]
1. UE is in the connected state.
2. UE measures one PCI and reports it to eNB but it does not belong to NRT(Neighbor Relation Table) in eNB.
3. eNB sends rrcConnectionReconfigurationMessage to read CGI for that PCI.
4. UE should read MIB/SIB1 to report CGI info to eNB.

In Step 4), In some materials on the web, UE should use IDLE periods to get SIB1, which is configured as DRX config in rrcConectionReconfigurationMesage. Because Measurement Gap is too short to read MIB/SIB1 and it's only for the measurement purpose.

[Question]
When UE is in the Connected State, How UE could use DRX configuration which is intended to use in IDLE state?

As my basic understanding, DRX configuration is to improve the battery life in idle mode.

Contact Us
+91 9880187415
sales@queryhome.net
support@queryhome.net
#280, 3rd floor, 5th Main
6th Sector, HSR Layout
Bangalore-560102
Karnataka INDIA.
QUERY HOME
...