To improve the channel capacity, a new Alamouti space-time block coding (STBC) multiple-input multiple-output (MIMO) system was employed for underwater communications.

A method and apparatus for performing uplink transmission in a multiple-input multiple-output (MIMO) single carrier frequency division multiple access (SC-FDMA) system are disclosed.

Multiple Input Multiple Output (MIMO) system with higher gains in channel capacity is one of the key technologies for future wireless communications.