Patent ID: 11909863
Assignee: TEXAS INSTRUMENTS INCORPORATED
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H  B  G  Y | IPC B  G  H

Claim 9:
10. A key fob comprising:
an antenna;
transceiver circuitry coupled to the antenna;
a memory configured to store a first key and instructions; and
a processor coupled to the transceiver circuitry and to the memory, the processor being configured to execute the instructions stored in the memory to cause the key fob to:
execute an authenticated challenge-response protocol with the first key;
receive, via the transceiver circuitry and the antenna, a first transmission from a control unit, wherein the first transmission includes an encrypted version of a second key that is encrypted by the first key;
decrypt the encrypted version of the second key using the first key to recover the second key, wherein the second key is a replacement key for the first key;
store the second key in the memory; and
execute the authenticated challenge-response protocol with the second key.