Intra-Node B Orthogonal Pilot Channel Structure for OFDM Radio Access in Evolved UTRA Downlink

This paper proposes an intra-node B orthogonal pilot channel structure employing a sector-specific orthogonal sequence and cell-specific (node B-specific) scrambling code for orthogonal frequency division multiplexing (OFDM)-based radio access in the E-UTRA downlink. This paper also proposes a sophisticated orthogonal pilot channel employing code division multiplexing (CDM) to separate sectored beams and distributed frequency division multiplexing (FDM) to separate streams (transmission antennas) in MIMO channel transmissions simultaneously. Successive simulation results verify the effectiveness of the proposed orthogonal pilot channel structures using distributed FDM among multiple streams and CDM between sectored beams. Furthermore, the simulation results also show that the average packet error rate (PER) performance using the proposed intra-node B orthogonal pilot channel is significantly improved compared to that of the conventional structure employing a random sequence, particularly for 16QAM and 64QAM modulations under high intra-node B interference-to-desired signal power ratio conditions