US 12,341,638 B2
OFDM time domain windowing method and apparatus
Qiaoyu Wang, Shenzhen (CN); Xing Liu, Shenzhen (CN); Dingming Zhang, Shenzhen (CN); and Dong Li, Shenzhen (CN)
Assigned to SANECHIPS TECHNOLOGY CO., LTD., Shenzhen (CN)
Appl. No. 17/776,578
Filed by SANECHIPS TECHNOLOGY CO., LTD., Shenzhen (CN)
PCT Filed Nov. 13, 2020, PCT No. PCT/CN2020/128767
§ 371(c)(1), (2) Date May 12, 2022,
PCT Pub. No. WO2021/093862, PCT Pub. Date May 20, 2021.
Claims priority of application No. 201911114928.1 (CN), filed on Nov. 14, 2019.
Prior Publication US 2022/0385510 A1, Dec. 1, 2022
Int. Cl. H04L 27/26 (2006.01); H04L 5/00 (2006.01)
CPC H04L 27/2607 (2013.01) [H04L 5/0007 (2013.01); H04L 27/2628 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An orthogonal frequency division multiplexing (OFDM) time domain windowing method, comprising:
parsing current OFDM symbol data according to a configuration task, and performing an inverse fast fourier transform (IFFT) processing on the current OFDM symbol data to obtain IFFT data;
adding a cyclic prefix (CP) to the IFFT data; and
determining a time domain windowing mode of the current OFDM symbol data according to the configuration task, performing a windowing operation on IFFT data added with the CP according to the determined time domain windowing mode, and outputting IFFT data after performing the windowing operation;
wherein performing the windowing operation on the IFFT data added with the CP according to the determined time domain windowing mode comprises:
in a case where the time domain windowing mode is a first windowing mode, acquiring data with a length of A0 from a head of a previous OFDM symbol to be copied as a cyclic suffix, and forming a data segment B1 by the cyclic suffix and last data with a length of A0 of the previous OFDM symbol; acquiring data with the length of A0 from a head of the CP of a current OFDM symbol and then acquiring data with the length of A0 before the CP to form a data segment A2, wherein a length of 2×A0 is equal to a length of the CP; multiplying the data segment A2 by a rising window coefficient to obtain windowed data of the data segment A2, multiplying the data segment B1 by a falling window coefficient to obtain windowed data of the data segment B1, and superposing the windowed data of the data segment A2 and the windowed data of the data segment B1 to obtain a data segment C; and replacing the last data with the length of A0 of the previous OFDM symbol with data with a front length of A0 of the data segment C, and replacing data with the front length of A0 of the CP of the current OFDM symbol with data with a rear length of A0 of the data segment C;
in a case where the time domain windowing mode is a second windowing mode, acquiring data with a length of 2×A0 from a head of a previous OFDM symbol to be copied as a cyclic suffix data segment B1, wherein the length of 2×A0 is less than or equal to a length of the CP; acquiring a data segment A1 with the length of 2×A0 from a head of the CP of a current OFDM symbol; and multiplying the data segment A1 by a rising window coefficient to obtain windowed data of the data segment A1, multiplying the data segment B1 by a falling window coefficient to obtain windowed data of the data segment B1, and superposing the windowed data of the data segment A1 and the windowed data of the data segment B1 to obtain a data segment C, replacing the data segment A1 of the current OFDM symbol with the data segment C, and reserving a remaining data segment A2 of the CP of the current OFDM symbol as the CP; or
in a case where the time domain windowing mode is a third windowing mode, acquiring a data segment A with a length of 2×A0 from a head of a CP of a current OFDM symbol, wherein the length of 2×A0 is less than a length of the CP; multiplying the data segment A by a rising window coefficient to replace data of the data segment A; and acquiring a data segment B with the length of 2×A0 from a last symbol of the current OFDM symbol, and multiplying the data segment B by a falling window coefficient to replace data of the data segment B.