This thesis expounds the key technology of the next generation mobile communication system-OFDM

it has good ability of avoiding multipath interferometry and high performance of frequency spectrum. Then we introduce the system which combines multicarrier multiplexing and CDMA

that is MC-CDMA

this system can support not only high data rate

but also high user capacity. MIMO technology which can enhance increase diversity and enhance system capacity combined MC-CDMA that is MIMO-MC-CDMA system is also mentioned in this document. Finally we simply introduce synchronization and channel estimation in MIMO-MC-CDMA.