Multi-user MIMO

Multi-user MIMO

In radio, multi-user MIMO (MU-MIMO) is a set of advanced MIMO (pronounced mee-moh or my-moh), multiple-input and multiple-output, technologies that exploit the availability of multiple independent radio terminals in order to enhance the communication capabilities of each individual terminal. To contrast, single-user MIMO only considers access to the multiple antennas that are physically connected to each individual terminal. MU-MIMO can be seen as the extended concept of space-division multiple access (SDMA) which allows a terminal to transmit (or receive) signal to (or from) multiple users in the same band simultaneously. PU2RC is a fundamental and practical MU-MIMO technology for broadcast and multiple access wireless communications.

Like the relationship between OFDM and OFDMA, MU-MIMO (and, similarly, SDMA) can be thought of as an extension of MIMO applied in various ways as a multiple access strategy. A significant difference is that the performance of MU-MIMO relies on precoding capability than OFDMA so that if the transmitter does not use precoding, the performance advantage of MU-MIMO is not achievable.

Multiple access MIMO, MIMO-SDMA, many transmit antenna MIMO-SDMA, Cooperative MIMO, Network MIMO and Ad-hoc MIMO are all family terminologies within MU-MIMO, as each of those technologies leverages multiple users as a degree of freedom in achieving successful radio transmission.

Read more about Multi-user MIMO:  Multi-user To Multi-user