Methods and apparatus for WLAN transmission

摘要

In a method for generating a PHY data unit for transmission via a communication channel, a modulation scheme is selected from a plurality of modulation schemes, information bits are encoded to generate encoded data using one or more encoders, and an interleaving parameter NCOL is selected using the selected modulation scheme. NCOL varies for different modulation schemes. The encoded data is interleaved, which includes entering the encoded data into NROW rows and reading the encoded data out in NCOL columns. The payload information of the PHY data unit is modulated according to the modulation scheme, and a plurality of OFDM symbols is formed based on the modulated payload information.

主权项

1. A method, implemented in a communication device, for generating a physical layer (PHY) data unit for transmission via a communication channel, the method comprising:
selecting, in the communication device, a modulation scheme from a plurality of modulation schemes; encoding, in the communication device, information bits to generate encoded data using one or more encoders; selecting, in the communication device, a number of spatial streams NSS; parsing, in the communication device, the encoded data into the number of spatial streams NSS; selecting, in the communication device, a first interleaving parameter NCOL ; selecting, in the communication device, a second interleaving parameter NROT using the selected number of spatial streams NSS, wherein NROT varies for different numbers of spatial streams; interleaving, in the communication device, the encoded data, including entering the encoded data into a matrix having an integer number of rows equal to NROW and an integer number of columns equal to NCOL , reading the encoded data out in the NCOL columns, and applying a frequency rotation r according to
r=(j−f*NROT*NBPSCS(iSS)) mod NCBPSS(iSS)where iSS is a spatial stream index, NCBPSS(iSS) is a number of coded bits per symbol for an iSS-th spatial stream, NBPSCS(iSS) is a number of coded bits per subcarrier for the iSS-th spatial stream, j=0, 1, . . . , NCBPSS(iSS)−1, and f is an integer that varies based on the spatial stream index iSS; modulating, in the communication device, payload information of the PHY data unit according to the modulation scheme, wherein the payload information includes the interleaved encoded data; and forming, in the communication device, a plurality of orthogonal frequency division multiplex (OFDM) symbols based on the modulated payload information.