HSUPA Code Allocation

HSUPA is the 3gpp release 6 featue which is basically enhancement in up-link data rate. There are multiple aspects of this feature but we will only discuss code allocation at phy in this blog post.

Here are the new physical channels added in HSUPA in UL and DL directions:


UL(UE to UTRAN) : 

• E-DPDCH

      Its an uplink Data channel which carries UE data to the NodeB. Could be 
      maximum up to 4.  the max code can be used like this 2SF2 + 2SF4.
      Two EDPDCH can use Spreading Factor 2 and two can use Spreading
      Factor 4.

• E-DPCCH

      It's an UL control channel which is used to carry control information related
      to the EDPDCH Data channels. There could be only 1 EDPCCH. And the
      channelization code and Spreading Factor is fixed for this channel.


DL(UTRAN to UE):

E-AGCH This channel carries Absolute grant, Fixed SF and Fixed Channelization code

E-RGCH: This channel is used to carry Relative grant

E-HICH: This channel is used to carry HARQ ACK/NAK information

Code and Spreading Factor for  E-DPDCH is not fixed but code for rest of the channels are fixed.

TBD ....