A frame format for high data throughput wireless local area network transmissions includes a first preamble segment, a second preamble segment, and a variable length data segment. The first preamble segment includes a first training sequence, a second training sequence, and a high throughput channel indication, wherein the first training sequence is within a first set of subcarriers of a channel and the second training sequence is within a second set of subcarriers of the channel, wherein the first set of subcarriers is a subset of the second set of subcarriers. The second preamble segment includes a third training sequence within a third set of subcarriers of the channel, wherein the second set of subcarriers is a subset of the third set of subcarriers. The variable length data segment utilizes the third set of subcarriers to convey data.