Investigations on ifdma signal detection problems in multipath fading channel

Abstract

New interleaving architectures for single and multiple data stream transmissions for an Interleaved Frequency Division Multiple Access (IFDMA) system are proposed. Peak-to-Average Power Ratio (PAPR) and Carrier Frequency Offset (CFO) analysis are done for the proposed methods. The proposed methods promise negligible Inter-Symbol Interference (ISI) and also attain multipath orthogonality. The proposed interleaving scheme for single data stream transmission equalizes ISI effectively compared to conventional interleaving adopted in the IFDMA system. In this method, the same spreading vector is used for each user. The Monte Carlo simulations executed for the proposed interleaving scheme with maximal ratio combining report excellent performance compared to the conventional interleaving scheme with minimum mean square error frequency domain equalization. The proposed interleaving scheme for multiple data stream transmission exploits the full benefits of the maximal length sequence, thereby allowing multiuser to transmit multiple data streams simultaneously over the fading channel. Compared to the single data stream transmission, the data rate for multiple data stream transmission is improved proportionally to the increase in the number of data streams transmitted. newline