Tone plan for LTF compression

An apparatus for wireless communication, comprising:

• means for transmitting user data in a plurality of first symbols, wherein each first symbol of the plurality of first symbols is a data symbol, wherein each first symbol of the plurality of first symbols has a first symbol duration, a first frequency bandwidth, and a first tone plan, wherein the first tone plan comprises a first valid start tone index, a first valid end tone index, and a first set of direct current (DC) tones;
• and
• means for transmitting a long training field (LTF) in a plurality of second symbols, wherein each second symbol of the plurality of second symbols is an LTF symbol, wherein each second symbol of the plurality of second symbols has a second symbol duration that is less than the first symbol duration, a second frequency bandwidth, and a second tone plan, wherein the second tone plan comprises a second valid start tone index, a second valid end tone index, and a second set of DC tones, wherein the second valid start tone index is a function of the first valid start tone index, the second valid end tone index is a function of the first valid end tone index, and the first symbol duration is two times greater than the second symbol duration, and wherein at least one of:
• (i) the first and second frequency bandwidths are 20 megahertz, the first valid start tone index is −122, the first valid end tone index is 122, the second valid start tone index is −61, and the second valid end tone index is 61,
• (ii) the first and second frequency bandwidths are 40 megahertz, the first valid start tone index is −250, the first valid end tone index is 250, the second valid start tone index is −125, and the second valid end tone index is 125, or
• (iii) the first and second frequency bandwidths are 80 megahertz, the first valid start tone index is −506, the first valid end tone index is 506, the second valid start tone index is −253, and the second valid end tone index is 253.

An apparatus for wireless communication, comprising:

• a memory;
• and
• at least one processor coupled to the memory, wherein the at least one processor is configured to:
• transmit user data in a plurality of first symbols, wherein each first symbol of the plurality of first symbols is a data symbol, wherein each first symbol of the plurality of first symbols has a first symbol duration, a first frequency bandwidth, and a first tone plan, wherein the first tone plan comprises a first valid start tone index, a first valid end tone index, and a first set of direct current (DC) tones;
• and
• transmit a long training field (LTF) in a plurality of second symbols, wherein each second symbol of the plurality of second symbols is an LTF symbol, wherein each second symbol of the plurality of second symbols has a second symbol duration that is less than the first symbol duration, a second frequency bandwidth, and a second tone plan, wherein the second tone plan comprises a second valid start tone index, a second valid end tone index, and a second set of DC tones, wherein the second valid start tone index is a function of the first valid start tone index, the second valid end tone index is a function of the first valid end tone index, and the first symbol duration is two times greater than the second symbol duration:
• and wherein at least one of:
• (i) the first and second frequency bandwidths are 20 megahertz, the first valid start tone index is −122, the first valid end tone index is 122, the second valid start tone index is −61, and the second valid end tone index is 61,
• (ii) the first and second frequency bandwidths are 40 megahertz, the first valid start tone index is −250, the first valid end tone index is 250, the second valid start tone index is −125, and the second valid end tone index is 125, or
• (iii) the first and second frequency bandwidths are 80 megahertz, the first valid start tone index is −506, the first valid end tone index is 506, the second valid start tone index is −253, and the second valid end tone index is 253.

A non-transitory computer-readable medium having code stored thereon that, when executed, causes at least one processor of a wireless device to:

• transmit user data in a plurality of first symbols, wherein each first symbol of the plurality of first symbols is a data symbol, wherein each first symbol of the plurality of first symbols has a first symbol duration, a first frequency bandwidth, and a first tone plan, wherein the first tone plan comprises a first valid start tone index, a first valid end tone index, and a first set of direct current (DC) tones;
• and
• transmit a long training field (LTF) in a plurality of second symbols, wherein each second symbol of the plurality of second symbols is an LTF symbol, wherein each second symbol of the plurality of second symbols has a second symbol duration that is less than the first symbol duration, a second frequency bandwidth, and a second tone plan, wherein the second tone plan comprises a second valid start tone index, a second valid end tone index, and a second set of DC tones, wherein the second valid start tone index is a function of the first valid start tone index, the second valid end tone index is a function of the first valid end tone index, and the first symbol duration is two times greater than the second symbol duration, and wherein at least one of:
• (i) the first and second frequency bandwidths are 20 megahertz, the first valid start tone index is −122, the first valid end tone index is 122, the second valid start tone index is −61, and the second valid end tone index is 61,
• (ii) the first and second frequency bandwidths are 40 megahertz, the first valid start tone index is −250, the first valid end tone index is 250, the second valid start tone index is −125, and the second valid end tone index is 125, or
• (iii) the first and second frequency bandwidths are 80 megahertz, the first valid start tone index is −506, the first valid end tone index is 506, the second valid start tone index is −253, and the second valid end tone index is 253.