US 12,137,339 B2
Ultra-wideband communication node and method for contention based ranging
Srivathsa Masthi Parthasarathi, Bangalore (IN); and Stefan Lemsitzer, Stainz (AT)
Assigned to NXP B.V., Eindhoven (NL)
Filed by NXP B.V., Eindhoven (NL)
Filed on Jan. 28, 2022, as Appl. No. 17/649,247.
Claims priority of application No. 202111005873 (IN), filed on Feb. 11, 2021.
Prior Publication US 2022/0256338 A1, Aug. 11, 2022
Int. Cl. H04L 29/06 (2006.01); H04L 9/08 (2006.01); H04L 9/40 (2022.01); H04W 12/037 (2021.01); H04W 12/0431 (2021.01)
CPC H04W 12/037 (2021.01) [H04L 9/0866 (2013.01); H04L 9/0869 (2013.01); H04L 63/0869 (2013.01); H04W 12/0431 (2021.01); H04L 2209/80 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An ultra-wideband, UWB, communication node comprising:
a UWB communication unit configured to
transmit one or more messages to a plurality of external responder nodes, wherein the one or more messages include a definition of a contention period, and the plurality of external responder nodes includes a first external responder node and a second external responder node,
receive a first response from the first external responder node during a first time slot within the contention period, wherein the first response includes a first encrypted response header and a first encrypted response payload, and
receive a second response from the second external responder node during a second time slot of within the contention period, wherein the second encrypted response includes a second response header and a second encrypted response payload; and
a processing unit coupled to the UWB communication unit, wherein the processing unit is configured to
decrypt the first encrypted response header using a common cryptographic session key to determine a first unique identifier that identifies the first external responder node,
determine, based on the first unique identifier, a first responder-specific cryptographic session key that is a first unique key known by the UWB communication node and the first external responder node,
decrypt the first encrypted response payload using the first responder-specific cryptographic session key to determine a timestamp of the first response,
decrypt the second encrypted response header using the common cryptographic session key to determine a second unique identifier that identifies the second external responder node, wherein the second unique identifier is different from the first unique identifier,
determine, based on the second unique identifier, a second responder-specific cryptographic session key that is a second unique key known by the UWB communication node and the second external responder node, wherein the second unique key is different from the first unique key, and
decrypt the second encrypted response payload using the second responder-specific cryptographic session key to determine a timestamp of the second response.