Channel Estimation Schemes for OFDM Relay-Assisted Systems

The aim of this paper is to adapt and evaluate the performance of two classical pilot-aided channel estimation schemes designed for OFDM systems: least square and minimum mean square error, in a relay-assisted scenario. We consider the amplify-and-forward, which is the simplest relay protocol for cooperative systems. Also, we consider the use of a single antenna at all the terminals: base station, user terminal and relay node. In our scenario, it is assumed that some of the user terminals deployed in a certain area could act as relaying-able terminals for the communications of other users. In this communication we show that the classical channel estimation techniques designed for conventional wireless communications can be extended for relay-assisted based systems under some modifications.