Abstract: Apparatus and methods for conducting communication over a wireless or other network using a multi-carrier energy-spreading approach. In one embodiment, an energy-spreading technique (EST) is applied within a multi-carrier or MC-CDMA system to improve signal detection performance and diversity. Significant improvements in Eb/N0 are achieved for both indoor and urban paradigms over systems without such EST capability. In another variant, a code-divided system with two transmit antennas is disclosed having a diversity code (e.g., Alamouti code) used to obtain enhanced transmit diversity. Another variant incorporates a “symbol shuffling” scheme (together with the aforementioned EST) to enhance diversity and performance. The symbol shuffling scheme and diversity code may also be combined to provide a matched filter bound (MFB) for systems with four or more antennas. Exemplary base station and subscriber (e.g.