US 11,700,162 B2
Peak-to-average-power reduction for OFDM multiple access
Steve Shattil, Cheyenne, WY (US)
Assigned to Tybalt, LLC, Boulder, CO (US)
Filed by Genghiscomm Holdings, LLC, Boulder, CO (US)
Filed on Apr. 30, 2021, as Appl. No. 17/245,297.
Application 17/245,297 is a continuation of application No. 16/779,657, filed on Feb. 2, 2020, granted, now 11,018,918.
Application 16/779,657 is a continuation of application No. 15/988,898, filed on May 24, 2018, granted, now 10,637,705, issued on Apr. 28, 2020.
Claims priority of provisional application 62/536,955, filed on Jul. 25, 2017.
Claims priority of provisional application 62/527,603, filed on Jun. 30, 2017.
Claims priority of provisional application 62/510,987, filed on May 25, 2017.
Prior Publication US 2021/0250217 A1, Aug. 12, 2021
Int. Cl. H04L 27/26 (2006.01); H04L 1/1829 (2023.01); H04B 7/06 (2006.01); H04B 7/0456 (2017.01); H04W 72/20 (2023.01); H04L 5/00 (2006.01)
CPC H04L 27/2636 (2013.01) [H04B 7/0456 (2013.01); H04B 7/0632 (2013.01); H04L 1/1861 (2013.01); H04W 72/20 (2023.01); H04L 5/0007 (2013.01)] 27 Claims
OG exemplary drawing
 
1. An apparatus, comprising:
a code-division multiplexer configured to assign a different codeword set to each of a plurality of data streams, each codeword set comprising a different one of a plurality of spread-Discrete Fourier Transform (DFT) code division multiple-access channels;
a DFT spreader configured to spread the each of the plurality of data streams with its assigned codeword set to produce a plurality of DFT-spread data symbols;
a mapper configured to map the plurality of DFT-spread data symbols to a plurality of Orthogonal Frequency Division Multiplexing (OFDM) subcarriers;
an inverse discrete Fourier transform (IDFT) configured to modulate the plurality of DFT-spread data symbols onto the plurality of OFDM subcarriers to generate an OFDM signal; and
a cyclic-prefix appender configured to append a cyclic prefix to the OFDM signal to produce a transmission signal; wherein the code-division multiplexer and the DFT spreader configure the OFDM signal to have a low peak-to-average-power ratio (PAPR); and wherein the cyclic-prefix appender produces the cyclic prefix from the OFDM signal to provide the transmission signal with a low PAPR.