Systems and methods for implementing an OFDMA LTF design for wireless network communication

1. A method for aligning high efficiency long training fields (“HE-LTF”) for data corresponding to a plurality of users, the method comprising:

obtaining, at a wireless transmitter, data for transmission to a plurality of users via a plurality of wireless channels;

determining a respective number of spatial streams for each user of the plurality of users for transmission via a data frame;

determining a size of a template matrix, wherein a first number of columns of the template matrix corresponds to at least a maximum number of spatial streams among the plurality of users and a first number of rows of the template matrix corresponds to at least the maximum number of spatial streams among the plurality of users;

accessing, from memory, the template matrix of the determined size;

generating a respective spatial mapping matrix for each user of the plurality of users based on the template matrix, wherein each respective spatial mapping matrix comprises the first number of columns in the template matrix, and wherein each respective matrix comprises a second number of rows equal to the respective number of spatial streams;

generating, based on the respective spatial matrix for each of the plurality of users, the data frame comprising aligned HE-LTF symbols; and

transmitting, via the wireless transmitter, the data frame via the plurality of wireless channels to the plurality of users.

2. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 1 , wherein determining the size of the template matrix comprises:

comparing the total number of spatial streams corresponding to the plurality of users to a plurality of predefined number of HE-LTF symbols; and

determining a predefined number of HE-LTF symbols of the plurality of predefined number of HE-LTF symbols that is equal to or greater than the maximum number of spatial streams.

3. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 2 , wherein the plurality of predefined number of HE-LTF symbols comprises 1, 2, 4, 6, and 8.

4. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 2 , wherein determining the predefined number of HE-LTF symbols comprises determining a minimum predefined number of HE-LTF symbols among the plurality of predefined number of HE-LTF symbols that is equal to or greater than the maximum number of spatial streams.

5. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 1 , wherein generating the respective spatial mapping matrix for each user of the plurality of users based on the template matrix comprises:

generating the respective spatial mapping matrix with the number of columns in the template matrix and with the number of rows equal to the respective number of spatial streams; and

populating the rows of the respective matrix with the corresponding row of the template matrix.

6. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 1 , wherein at least the maximum number of spatial streams among the plurality of users exceeds 8, and wherein generating a respective spatial mapping matrix for each user of the plurality of users based on the template matrix comprises:

accessing, from memory, a predefined 8×8 template matrix;

generating an extended spatial matrix, wherein the extended spatial matrix comprises:

a second number of columns that corresponds to at least the maximum number of spatial streams among the plurality of users that extends beyond 8; and

a third number of rows is 8; and

populating the extended spatial matrix based on the predefined 8×8 template matrix.

7. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 6 , wherein populating the extended spatial matrix based on the predefined 8×8 template matrix comprises:

determining a multiplier of 8 such that multiplying the multiplier by 8 is less than at least the maximum number of spatial streams among the plurality of users;

populating a partial number of the second number of columns by horizontally concatenating the predefined 8×8 matrix with itself a number of times equivalent to the multiplier to generate a partial extended spatial matrix; and

populating a remaining number of the second number of columns by horizontally concatenating the partial extended spatial matrix with a portion of the predefined 8×8 matrix, wherein:

the portion of the predefined 8×8 matrix comprises a third number of columns corresponding to the remaining number and the third number of rows; and

the partial number and the remaining number add up to the second number of columns.

8. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 1 , wherein each respective row of a given respective matrix is orthogonal to each other respective row of the given respective matrix.

9. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 1 , wherein generating, based on the respective spatial matrix for each of the plurality of users, the data frame comprising aligned HE-LTF symbols comprises calculating a dot product of a beamforming matrix and the respective spatial matrix.

10. The method for aligning HE-LTF for data corresponding to the plurality of users of claim 1 , wherein generating, based on the respective spatial matrix for each of the plurality of users, the data frame comprising aligned HE-LTF symbols comprises:

defining an alignment number of HE-LTF symbols to be equal to or greater than the maximum number of spatial streams among the plurality of users; and

determining the number of columns of the respective spatial matrix for each of the plurality of users is equivalent to the alignment number of HE-LTF symbols.

11. A system for aligning high efficiency long training fields (“HE-LTF”) for data corresponding to a plurality of users, the system comprising:

a wireless transmitter configured to:

obtain, at a wireless transmitter, data for transmission to a plurality of users via a plurality of wireless channels;

control circuitry coupled to the wireless transmitter, configured to:

determine a respective number of spatial streams for each user of the plurality of users for transmission via a data frame;

determine a size of a template matrix, wherein a number of columns of the template matrix corresponds to at least a maximum number of spatial streams among the plurality of users and a first number of rows of the template matrix corresponds to at least the maximum number of spatial streams among the plurality of users;

access, from memory, the template matrix of the determined size;

generate a respective spatial mapping matrix for each user of the plurality of users based on the template matrix, wherein each respective spatial mapping matrix comprises the first number of columns in the template matrix, and wherein each respective matrix comprises a second number of rows equal to the respective number of spatial streams;

generate, based on the respective spatial matrix for each of the plurality of users, the data frame comprising aligned HE-LTF symbols; and

the wireless transmitter further configured to:

transmit the data frame via the plurality of wireless channels to the plurality of users.

12. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 11 , wherein the control circuitry is further configured to determine the size of the template matrix by:

comparing the total number of spatial streams corresponding to the plurality of users to a plurality of predefined number of HE-LTF symbols; and

determining a predefined number of HE-LTF symbols of the plurality of predefined number of HE-LTF symbols that is equal to or greater than the maximum of spatial streams.

13. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 12 , wherein the plurality of predefined number of HE-LTF symbols comprises 1, 2, 4, 6, and 8.

14. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 12 , wherein determining the predefined number of HE-LTF symbols comprises determining a minimum predefined number of HE-LTF symbols among the plurality of predefined number of HE-LTF symbols that is equal to or greater than the maximum number of spatial streams.

15. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 11 , wherein the control circuitry is further configured to generate the respective spatial mapping matrix for each user of the plurality of users based on the template matrix by:

generating the respective spatial mapping matrix with the number of columns in the template matrix and with the number of rows equal to the respective number of spatial streams; and

populating the rows of the respective matrix with the corresponding row of the template matrix.

16. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 11 , wherein at least the maximum number of spatial streams among the plurality of users exceeds 8, and wherein the control circuitry is further configured to generate a respective spatial mapping matrix for each user of the plurality of users based on the template matrix by:

accessing, from memory, a predefined 8×8 template matrix;

generating an extended spatial matrix, wherein the extended spatial matrix comprises:

a second number of columns that corresponds to at least the maximum number of spatial streams among the plurality of users that extends beyond 8; and

a third number of rows is 8; and

populating the extended spatial matrix based on the predefined 8×8 template matrix.

17. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 16 , wherein the control circuitry is configured to populate the extended spatial matrix based on the predefined 8×8 template matrix by:

determining a multiplier of 8 such that multiplying the multiplier by 8 is less than at least the maximum number of spatial streams among the plurality of users;

populating a partial number of the second number of columns by horizontally concatenating the predefined 8×8 matrix with itself a number of times equivalent to the multiplier to generate a partial extended spatial matrix; and

populating a remaining number of the second number of columns by horizontally concatenating the partial extended spatial matrix with portion of the predefined 8×8 matrix, wherein:

the portion of the predefined 8×8 matrix comprises a third number of columns corresponding to the remaining number and the third number of rows; and

the partial number and the remaining number add up to the second number of columns.

18. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 11 , wherein each respective row of a given respective matrix is orthogonal to each other respective row of the given respective matrix.

19. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 11 , wherein the control circuitry is further configured to generate, based on the respective spatial matrix for each of the plurality of users, the data frame comprising aligned HE-LTF symbols by calculating a dot product of a beamforming matrix and the respective spatial matrix.

20. The system for aligning HE-LTF for data corresponding to the plurality of users of claim 11 , wherein the control circuitry is further configured to generate, based on the respective spatial matrix for each of the plurality of users, the data frame comprising aligned HE-LTF symbols by:

defining an alignment number of HE-LTF symbols to be equal to or greater than the maximum number of spatial streams among the plurality of users; and

determining the number of columns of the respective spatial matrix for each of the plurality of users is equivalent to the alignment number of HE-LTF symbols.