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

Facebook Login
Site Registration

In TDD-LTE how time slot allocation being done for both uplink and downlink. Any idea?

+2 votes
512 views
In TDD-LTE how time slot allocation being done for both uplink and downlink. Any idea?
posted May 20, 2014 by Aman

Share this question
Facebook Share Button Twitter Share Button Google+ Share Button LinkedIn Share Button Multiple Social Share Button

1 Answer

0 votes

Time Slot Allocation for Uplink and Downlink – TDD specific

The time division nature of LTE TDD will also require radio engineers to consider how time slots are shared between uplink and downlink based on both customer input as well as commercial users usage pattern between uplink and downlink in that country. This will have a direct impact on the EUTRAN capacity. There are 7 time sharing configuration between Uplink and Downlink in LTE TDD as defined by 3GPP. They are shown in the figure below and in summary, they are (DL : UL) – 1:3 or 2:2 or 3:1 or 2:1 or 7:2 or 8:1 or 3:5

enter image description here

Besides time sharing configuration, there is also a need to define how uplink and downlink pilots are configured based on the Guard band requirement. The guard band duration is also a direct result of propagation delay requirement due to the designated cell coverage radius. Inadequate guard band provisioning will result in direct interference between users within the same cell due to difference in signal delay arrival. 3GPP has defined 9 different guard period configuration schemes for Operator to choose. They are listed in the figure above.

Cyclical Prefix Allocation:

In order to accommodate extended propagation delay (e.g. due to large cell radius coverage), a lower order cyclic prefix value of 6 can be used instead of the common value of 7. This will result in the reduction of OFDM symbols that can be carried per time slot and therefore reducing the overall sector capacity.

answer May 21, 2014 by Prachi Sharma
Similar Questions
+4 votes

Which are the nodes involve to maintains QoS in term of lte and ToS w.r.t IP protocl for an ip packet in dwn & up link direction?

+1 vote

I don't know the complete use of CQI at eNodeB. Does it impact only downlink scheduling parameters or also considered while granting uplink resources ?

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
...