The stream assignment of {3, 3, 3, 2} is depicted in FIG. 3, where streams 301-311 correspond to the 11 streams to be transmitted. The streams are depicted as arrows representing a frequency response of a signal to be transmitted for each stream, where the signals are labeled with the associated stream number (e.g., the signal to be sent through stream 1 is labeled with a “1” in the arrows). The signals for the 1st, 2nd, and 3rd streams are multiplexed onto set 1 tones {0, 4, 8, . . . , 252}. The signals for the 4th, 5th, and 6th streams are multiplexed onto set 2 tones {1, 5, 9, . . . , 253}. The signals for the 7th, 8th, and 9th streams are multiplexed onto set 3 tones {2, 6, 10, . . . , 254}. The signals for the 10th and 11th streams are multiplexed onto set 4 tones {3, 7, 11, . . . , 255}.
The HE-LTF symbols are generated by preamble generation 101, in some embodiments, according to the assignment of streams to tones and standard P-matrix that is selected according to the maximum number of streams transmitted across a set of tones (e.g., select a standard 4×4 P-matrix for the set {3, 3, 3, 2} because a 4×4 P-matrix is used for up to 4 streams). The signal transmitted by transmitter 102 is, in some embodiments, given by
y=HNr×NtQNt×NstsPNsts
