 Feedback Modes [2] MIMO Parameters MIMO Parameters Feedback Type of Feedback outside Open-loop inside Open-loop Resource Unit Components MIMO Region MIMO Region Mode 0 Open-loop SU- Spatial rate and MIMO mode 0 and MIMO mode 0 and MIMO SFBC/ wideband CQI MIMO mode 1 and MIMO mode 1 with Spatial flexible adaptation flexible adaptation Multiplexing between the two between the two (DRU and mini- modes: modes: band LRU) R=1 (SFBC) CQI R = 1 (SFBC) CQI Sounding- 2 < R < 4 (spatial R = 2 (spatial based closed- multiplexing) CQI multiplexing) CQI loop SU-MIMO Ns = 2 and MU-MIMO (spatial multiplexing) when using DRU Ns > 2 (spatial multiplexing) when using mini-band LRU For sounding-based closed-loop SU-MIMO and MU-MIMO (R=1): SFBC CQI Mode 1 Open-loop SU- Wideband CQI MIMO mode 5 MIMO CDR R = 1/2 (mini-band LRU) Mode 2 Open-loop SU- Spatial rate, MIMO mode 1 MIMO mode 5 MIMO spatial sub-band CQI, 1 < R < 8 R = 1/2 multiplexing and sub-band (sub-band LRU) selection Mode 3 Closed-loop Spatial Rate, MIMO mode 2 SU-MIMO sub-band CQI, 1 < R < 8 (sub-band LRU) sub-band PMI, sub-band selection, and wideband correlation matrix Mode 4 Closed-loop Spatial rate, MIMO mode 2 (Ns < 4 ) SU-MIMO (mini- wideband CQI, band LRU) wideband PMI, and wideband correlation matrix Mode 5 Open-loop Sub-band CQI, MIMO mode 3 MIMO mode 3 MU-MIMO sub-band (sub-band LRU) selection, and MIMO stream indicator 10.5 IEEE 802. 16m downlink MIMO schemes Table 10-25 MIMO Feedback Modes [2] Continued MIMO Parameters MIMO Parameters Feedback Type of Feedback outside Open-loop inside Open-loop Resource Unit Components MIMO Region MIMO Region Mode 6 Closed-loop MU Sub-band CQI, MIMO mode 4 sub-band PMI, (localized: sub- sub-band band LRU) selection, and wideband correlation matrix Mode 7 Closed-loop Wideband CQI, MIMO mode 4 MU-MIMO wideband PMI, (mini-band LRU) and wideband correlation matrix scheme in localized permutation zones to facilitate frequency selective scheduling. In this mode, the MS feeds back the sub-band selection, MIMO stream indicator, and t