Abstract: Methods and apparatuses for adjacent channel interference mitigation during the acquisition phase in OFDM communications use a Discrete Fourier Transform (DFT) to detect the energy of a received channel without adding latency. In particular embodiments, the communications are vehicular OFDM communications and the DFT is a sliding DFT of variable length. In a typical acquisition procedure, RF gain is set based on received total energy, which includes energies of the received and adjacent channels. A modified state machine waits until the energy of a received channel is detected, then the RF gain is adjusted to fulfill an enhanced adjacent channel rejection criterion requirement.