US 12,074,683 B1
Configurable orthogonal frequency division multiplexing (OFDM) signal and transmitter and receiver for satellite to user terminal downlink communications
Martin S. McCormick, El Segundo, CA (US); Torbjorn Larsson, Escondido, CA (US); Alazar Tamrat, Torrance, CA (US); Jeffrey C. Strait, Reno, NV (US); Chen Chen, Irvine, CA (US); Philip J. Treigherman, Fountain Valley, CA (US); Stephan O. Roche, Rancho Palos Verdes, CA (US); and Ronald Gottula, San Mateo, CA (US)
Assigned to Space Exploration Technologies Corp., Hawthorne, CA (US)
Filed by Space Exploration Technologies Corp., Hawthorne, CA (US)
Filed on Feb. 26, 2021, as Appl. No. 17/186,706.
Claims priority of provisional application 62/983,644, filed on Feb. 29, 2020.
Claims priority of provisional application 62/983,651, filed on Feb. 29, 2020.
Claims priority of provisional application 62/983,641, filed on Feb. 29, 2020.
Claims priority of provisional application 62/983,649, filed on Feb. 29, 2020.
Int. Cl. H04B 7/185 (2006.01); H04L 5/00 (2006.01); H04W 72/0453 (2023.01)
CPC H04B 7/18513 (2013.01) [H04L 5/0048 (2013.01); H04W 72/0453 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A modem configured to receive a transmitted waveform transmitted from a satellite (SAT) to a user terminal (UT), the modem comprising:
a receiver, on the UT, configured to receive the transmitted waveform from the SAT, to extract user data from the transmitted waveform and to transmit the user data to a computing device, the transmitted waveform comprising:
a unique word configured in a first time period of a burst in a radio frame;
a first channel estimation symbol configured in a second time period of the burst of the radio frame, the second time period adjacent to the first time period, the first channel estimation symbol being associated with first user data intended for the UT and covering a first channel estimation symbol set of frequency resources;
a first pilot subcarrier at a first frequency in a third time period of the burst in the radio frame;
a second pilot subcarrier at a second frequency in the third time period of the burst in the radio frame;
a first resource block comprising the first user data configured in the third time period and utilizing a first resource block set of frequency resources between the first pilot subcarrier and the second pilot subcarrier;
a second channel estimation symbol configured in the second time period of the burst of the radio frame, the second channel estimation symbol being associated with second user data intended for a second UT and covering a second channel estimation symbol set of frequency resources;
a third pilot subcarrier at a third frequency in the third time period of the burst in the radio frame;
a fourth pilot subcarrier at a fourth frequency in the third time period of the burst in the radio frame; and
a second resource block comprising the second user data configured in the third time period and utilizing a second resource block set of frequency resources between the third pilot subcarrier and the fourth pilot subcarrier; and
a delay component that causes the receiver to wait a delay time based on a distance of the UT from the SAT before extracting the first resource block from the burst in the radio frame.