Patent ID: 11943621
Assignee: TEXAS INSTRUMENTS INCORPORATED
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 13:
14. An apparatus, comprising:
a non-transitory memory storing application instructions; and
a processor coupled to the non-transitory memory and configured to execute the application instructions to cause the processor to:
determine a first value for a localization tone;
generate a modified localization tone such that, after whitening and encrypting, the modified localization tone returns to the first value;
insert the modified localization tone into a data packet at an application layer of a communication protocol stack, the modified localization tone preceding data of a payload of the data packet and having a last bit immediately preceding a first bit of the data of the payload;
whiten the data packet after inserting the modified localization tone into the data packet;
encrypt the data packet after inserting the modified localization tone into the data packet; and
transmit the data packet after the whitening and the encrypting the data packet, wherein to generate the modified localization tone comprises, the processor is further configured to:
perform a Decrypt_AES(IV,SK,array(bit_i)) process, wherein Decrypt_AES is an established algorithm according to the Advanced Encryption Standard (AES) encryption protocol, IV is an initialization vector, SK is a session key, and bit_i is the localization tone, and
for each bit of the modified localization tone,
estimate an output of a linear feedback shift register, and
perform an exclusive-OR operation of a constant value and the estimated output of the linear feedback shift register based on a respective bit of the modified localization tone being considered and a position of that respective bit of the modified localization tone in the data packet.