	US 11,855,825 B2
	IBOC compatible superposition modulation by independent modulators utilizing clipping noise from peak-to-average power reduction
Philipp Schmid, Hackett's Cove (CA)
Assigned to NAUTEL LIMITED, Hackett's Cove (CA)
Filed by Nautel Limited, Hackett's Cove (CA)
Filed on Jun. 23, 2022, as Appl. No. 17/848,132.
Application 17/848,132 is a continuation of application No. 17/162,592, filed on Jan. 29, 2021, granted, now 11,381,439.
Claims priority of application No. CA 3070530 (CA), filed on Jan. 30, 2020.
Prior Publication US 2023/0318898 A1, Oct. 5, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04K 1/02 (2006.01); H04L 25/03 (2006.01); H04L 25/49 (2006.01); H04L 27/26 (2006.01); H04L 27/18 (2006.01); H04H 40/18 (2008.01); H04L 5/02 (2006.01)

CPC H04L 27/2624 (2013.01) [H04H 40/18 (2013.01); H04L 5/023 (2013.01); H04L 27/183 (2013.01); H04H 2201/18 (2013.01)]

9 Claims

1. A radio transmission method comprising: transmitting an orthogonal frequency division multiplexing (OFDM) waveform signal to a plurality of receivers; the modulated signal for providing additional bandwidth to receivers capable of decoding a higher modulation while a main modulation of the OFDM waveform signal complies with signal quality specifications to be compatible with receivers capable of receiving the same, the transmitted OFDM waveform signal trading a peak-to-average power ratio (PAPR) reduction induced constellation noise of all or a subset of in-band on-channel (IBOC) carriers within the ODFM waveform with data carrying hierarchical modulation.