Methods and apparatus for including mode information in a wireless transmission frame, which is useful for system acquisition. In particular, a first information bit is provided in a preamble of a transmission frame, where the bit is configured to indicate that a wireless communication system is operating according to either a time division duplex (TDD) mode or a frequency division duplex (FDD) mode. The addition of a single bit minimally affects the resources of the preamble. Additionally, another bit resource already present in the preamble for normally communicating whether FDD transmissions are full duplex or half-duplex transmissions, may be further allocated to indicate partitioning information concerning TDD mode transmissions when the first bit indicates TDD mode, thus affording additional information communicated in the frame without increasing preamble resources.