摘要：Orthogonal Frequency Multiplexing (OFDM) is a multicarrier modulation technique which allows sub channel overlapping for efficient utilization of available frequency spectrum. Demand for high data rate wireless communication is rapidly increasing and there is a need for a technique which overcomes the problems like Intersymbol Interference (ISI) and frequency selective fading. OFDM overcomes the problems of high data rate wireless communication by converting high rate data stream in to number of parallel low rate data streams and this will be a suitable modulation/multiplexing technique for advanced wireless communication systems. In this paper, a review has been made, to detail the progress on OFDM since 1870, it also explains the basic building blocks of OFDM, Code Division Multiple Access (CDMA) and Multi Carrier Code Division Multiple Access (MC-CDMA) Schemes and how it could be modified suitably?, to carry additional confidential Information using steganography.
