Data Transmission Method and Communications Device

A communication device, comprising:

• a transceiver, the transceiver configured to receive a transmission frame sent by a first communication device, wherein the transmission frame comprises a first part and a second part;
• wherein the first part of the transmission frame comprises a preamble part of the transmission frame, and wherein the second part of the transmission frame comprises a data part of the transmission frame;
• wherein the preamble part of the transmission frame carries information required for the communication device to demodulate the second part of the transmission frame, wherein the preamble part of the transmission frame comprises a legacy short training field (L-STF), a legacy long training field (L-LTF), legacy signaling (L-SIG), and a high efficiency wireless local area network signaling (HEW-SIG), and wherein the HEW-SIG carries the information required for the communication device to demodulate the second part of the transmission frame;
• and
• wherein the first part of the transmission frame is sent by the first communication device by using a first quantity of subcarriers, wherein the second part of the transmission frame is sent by the first communication device by using a second quantity of subcarriers;
• the transceiver further configured to:
• receive the first part of the transmission frame by using Fourier transform of the first quantity;
• and
• receive the second part of the transmission frame by using Fourier transform of the second quantity, wherein transmission bandwidths used by the first part and the second part of the transmission frame are equal, wherein a spacing of the first quantity of subcarriers is greater than a spacing of the second quantity of subcarriers, and wherein the spacing of the first quantity of subcarriers is 312.5 kHz;
• and
• at least one processor, the at least one processor configured to acquire data information in the transmission frame.

A data transmission method, comprising:

• sending, by a first communication device, a transmission frame to a second communication device, wherein the transmission frame comprises a first part and a second part;
• wherein the first part of the transmission frame comprises a preamble part of the transmission frame, and wherein the second part of the transmission frame comprises a data part of the transmission frame;
• wherein the preamble part of the transmission frame carries information required for the second communication device to demodulate the second part of the transmission frame, wherein the preamble part of the transmission frame comprises a legacy short training field (L-STF), a legacy long training field (L-LTF), legacy signaling (L-SIG), and a high efficiency wireless local area network signaling (HEW-SIG), and wherein the HEW-SIG carries the information required for the second communication device to demodulate the second part of the transmission frame;
• wherein the first communication device sends the first part of the transmission frame by using a first quantity of subcarriers, wherein the first communication device sends the second part of the transmission frame by using a second quantity of subcarriers, and wherein the first quantity is not equal to the second quantity;
• and
• wherein transmission bandwidths used by the first part and the second part of the transmission frame are equal, wherein a spacing of the first quantity of subcarriers is greater than a spacing of the second quantity of subcarriers, and wherein the spacing of the first quantity of subcarriers is 312.5 kHz.