A method for wireless communication is provided. The method includes receiving, at a wireless device, a packet including a first field over a first number of tones, and a second field over a second number of tones. The second number of tones is greater than the first number of tones by a number of one or more edge tones carrying data. The method further includes determining at least one of a communication mode and a channel estimation based at least in part on the one or more edge tones carrying data.