1. A base station comprising: a transmit path circuitry configured to transmit downlink control information in a downlink control information (DCI) format to a subscriber station; and a receive path circuitry configured to receive multiple-input multiple-output (MIMO) feedback from the subscriber station in response to the downlink control information, wherein the MIMO feedback from the subscriber station is determined by two or more codepoints in the DCI format, and wherein one of the two or more codepoints indicates a rank-limited single user multiple-input multiple-output (SU-MIMO) feedback corresponding to a rank up to a maximum rank.