Methods, equipment, and communication systems based on circular division sequences

Abstract

This invention relates to a method, apparatus, and communication system based on a cyclically shifting diversity sequence. In this method, the first communication device generates a Physical Layer Protocol Data Utilization (PPDU) data unit and transmits the PPDU to the second communication device. This PPDU unit has a short training field (STF), a long training field (LTF), and a data field defined by a cyclic shift diversity sequence (CSD). After receiving the PPDU unit from the first communication device, the second communication device performs processing based on the PPDU unit. The CSD sequence has L elements. L is the maximum number of spatial data streams that the first and second communication devices support. The maximum number of spatial data streams is 16 or greater. According to this solution, the maximum number of spatial data streams is expanded to 16 or greater, improving system capacity and efficiency compared to a solution with a maximum of eight spatial data streams using conventional technology. Additionally, based on the maximum number of data lines in the expanded space, the corresponding CSD sequence is used in the STF field, LTF field, and data field to control the gain coefficient setting error for the Automatic Gain Control (AGC) scheme.