Hybrid carrier spread spectrum system based on 4-weighted fractional fourier transform

Spread Spectrum (SS) is a promising technique to resist interference in wireless communication system. In order to further improve this capability, this paper proposes a Hybrid Carrier (HC) SS system, combining 4-Weighted Fractional Fourier Transform (4-WFRFT) with SS technique. In this HC-SS system, due to the property of 4-WFRFT, the signal energy of proposed system is distributed on the time-frequency plane more evenly and symmetrically, compared with the existing Single-Carrier (SC) and Multi-Carrier (MC) spread spectrum systems. In the selective channel, the proposed method can split the interference to a more broad range in order to reduce the influence, resulting in the better system performance. In addition, proposed system can be seen as the convergence of the existing SS techniques, which is a main feature in future.