A base station for use in a wireless network capable of communicating with a plurality of mobile stations. The base station transmits to a first mobile station downlink subframes of OFDM symbols. Each downlink subframe comprises a plurality of resource blocks and is associated with a subframe (SF) type that is determined according to whether or not a PDSCH region of a resource block in a downlink subframe includes at least one of: 1) a cell-specific reference signal (CRS) resource element and 2) a channel-state-information reference signal (CSI-RS) resource element. The base station receives from the first mobile station at least one of COI, PMI, modulation scheme, and transport block size and interprets the received at least one of COI, PMI, modulation scheme, and transport block size according to a default SF type used by the first mobile station to determine the at least one of COI, PMI, modulation scheme, and transport block size.