New 2D-MC-DS-SS-CDMA Techniques Based on Two-Dimensional Orthogonal Complete Complementary Codes

In this paper we present some new concepts of 2D-MC-DS -SS-CDMA techniques based on two-dimensional orthogonal complete complementary codes (2D-OCCC). General benefits of 2D spreading in the time-frequency space include lower power spectral density, thus better low probability of detection (LPD) and low probability of intercept (LPI) property, higher jam resistance, etc. Additional benefits of CCC include features like offset stacked spreading, MAI free system and a high spectral efficiency. 2D-OCCC provides a wider range of freedom in positioning the code elements in a channel when compared to 1D-OCCC. The proposed systems and techniques combine the advantages of 2D spreading with the advantages of 2D-OCCC. Because 2D-OCCC has special requirements on transmission channels, we explored several possibilities of 2D channel definitions. According to these, new transmission strategies are proposed. Also partial solutions of the limited user count problem using 2D-OCCC are described.