Relay in LTE architecture

[Lea Itu]

Hi everyone.

I am doing this project with a mobile relay.

UE2  <======== eNb2 - UE1 <======== eNb1<=======EPC

The eNb1 and eNb2 are in different frequencies because eNb2 is located and moving within the eNb1 coverage area. The UE1 and eNb2 move together. The relay is done between the UE1 and eNb2 at the PDCP layer. I need to catch the packets at the PDCP layer on UE1 and forward them to the PDCP layer on eNb2. Finally eNb2 will transmit to UE2. Asume that UE2, UE1 and eNb2 are moving within a train.  

I see that I can catch the packet in UE1 at Lte-pdcp.cc   LtePdcp::DoReceivePdu (….) and. DoTransmitPdcpSdu(…), but I do not know how to send that packet to the eNb2.

I just need a guide about how to accomplish the transmission under this architecture. Should I modify the LlteHelper in order to perform this task?

Thanks in advance guys.

Cheers, 

Lea