In some embodiments, a method includes receiving, at a receiver of a first device via a channel of a communication medium, multiple data transmissions. Each data transmission of the multiple data transmissions has a guard interval of multiple guard intervals, wherein the multiple guard intervals have different lengths. The method includes determining, based on signal characteristics of the multiple data transmissions, the data transmission from among the multiple data transmissions having a preferred physical data rate. The method includes setting a length of an adjusted guard interval for the channel for data communication from a transmitter of a second device to the receiver of the first device via the communication medium, to a length of the guard interval for the data transmission having the preferred physical data rate.