User Plane Protocol Optimization in Cellular Networks with Decode-and-Forward Type of Relay

The use of relay stations in the cellular network is a good candidate method to enhance the cell edge data rate, and to provide homogeneous QoS experience for users in different locations. We discuss the decode-and-forward type relay station within the context of the 3GPP RLC/MAC layers. The emphasis is on proper RLC layer operation for the relay-enhanced-cell (REC). RLC layer evolvement in the future high data rate radio access network will first be discussed, then its performance in REC will be investigated, with or without it being implemented on the relay station. Simulations are conducted on the downlink for the future OFDMA-based relay network, from which we finally draw significant conclusions.