US 11,785,452 B2
Error correction code-based embedding in adaptive rate communication systems
Peter Michael Baab Harley, Annapolis, MD (US); Murali Tummala, Monterey, CA (US); and John Colin Mceachen, Carmel, CA (US)
Assigned to The Government of the United States of America, as represented by the Secretary of the Navy, Washington, DC (US)
Filed by The United States of America, as represented by the Secretary of the Navy, Arlington, VA (US)
Filed on Jan. 22, 2021, as Appl. No. 17/156,425.
Claims priority of provisional application 62/964,533, filed on Jan. 22, 2020.
Prior Publication US 2021/0227384 A1, Jul. 22, 2021
Int. Cl. H04W 12/037 (2021.01); H04W 12/0431 (2021.01); H04L 1/00 (2006.01); H04L 9/40 (2022.01); H04W 84/12 (2009.01); H03M 13/35 (2006.01); H03M 13/11 (2006.01)
CPC H04W 12/037 (2021.01) [H03M 13/1102 (2013.01); H03M 13/353 (2013.01); H04L 1/0002 (2013.01); H04L 1/0054 (2013.01); H04L 1/0061 (2013.01); H04L 63/04 (2013.01); H04W 12/0431 (2021.01); H04W 84/12 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for concealing information within error correction codes of adaptive rate wireless communication systems, the method comprising:
selecting a modulation and coding scheme with a more robust error correction capacity than needed by current channel conditions to increase a covert channel capacity of wireless communication systems;
encoding a hidden message with a pre-shared key that is known by a covert transmitter and a covert receiver; and
after a standard message is encoded by a transmitting station of the wireless communication systems, replacing codeword parity bits of codewords in the encoded standard message with the encoded hidden message at designated locations;
wherein before a receiving station of the wireless communication systems decodes the encoded standard message, a covert receiver:
extracts the embedded hidden message from the encoded standard message;
replaces bit values of the embedded hidden message with zero at the designated locations; and
decodes the extracted hidden message with the pre-shared key.