A multi-carrier transmission system configured to enable variable modulation order reception is contemplated. The system may be configured to facilitate delivery of high-speed data (HSD) over frequency division duplexing (FDD) and/or time division duplexing (TDD) infrastructures to a plurality of receiving devices. Signaling used to facilitate delivery of the HSD may be selectively and dynamically modulated according to performance capabilities of the receiving devices for a given transmission interval.