Theoretical and Experimental Design of an Alternative System to 2x2 MIMO for LTE Over 60 Km Directly Modulated RoF Link
Relay Nodes (RN) are used as an important structure to extend the coverage of the Third Generation Partnership Program's Long Term Evolution (3GPP-LTE). The promising technology as the interface between eNodeB (eNB) and RN is Radio-over-Fibre (RoF), due to its longer span transmission capability. In this paper, the authors propose an alternative technique to 2x2 Multiple-Input and Multiple-Output (MIMO) in LTE structure for transmission over 60 km directly modulated RoF link by introducing Frequency Division Multiplexing (FDM) for Orthogonal FDM (OFDM). The system is demonstrated theoretically and experimentally. In the baseband, Quadrature Phase Shift Keying (QPSK), 16-Quadrature Amplitude Modulation (QAM) and 64-QAM are considered as the Single Carrier Modulations (SCM) according to the LTE standard.