LTE-A system adopts CoMP technology to improve the performance of cell edge users and sector throughput

through joint scheduling and cooperative transmission of several cells and reducing the inter-cell interference.Random access procedure is a very important procedure in the mobile communication system

which establishes a connection between UE and network.It will be affected by the new transmission mode.This paper discusses the scenes and process of access

the resource allocation problem in resource request stage

and the handoff process in some cases

to put forward the evolution of these processes in CoMP environment.