Time-Multiplexed Chipset for Secure PEPS Ranging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Passive Entry Passive Start (PEPS) systems using narrow-band radios for car key positioning lack security and accuracy, particularly against phase manipulation and symbol level attacks, and are costly due to the need for separate sensors and adjacent signal transmitters.
Innovation Solution
Implementing a secure multi-carrier phase-based ranging method where sensing and adjacent signal transmission functionalities are shared on the same chipset, with time-multiplexing between sensors and transmitters, reducing the number of chipsets and cost while enhancing security through spatial randomization and frequency offset protection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If separate sensors and adjacent signal transmitters are used for PEPS positioning, then positioning accuracy is improved, but device complexity and cost increase
Solution Approach 1:
The patent merges the functions of sensing and adjacent signal transmission into a single chipset. The supporting chipset performs both receiving ranging signals for phase measurements and transmitting adjacent channel signals for security protection, eliminating the need for separate sensor chipsets and reducing overall system complexity while maintaining positioning accuracy
Solution Approach 2:
The supporting chipset is designed with multi-functionality, capable of operating as both a receiver for phase-based ranging and a transmitter for adjacent signal protection. This universal design allows one chipset to fulfill multiple roles that previously required separate dedicated components
2Device complexity
If traditional AoA/DoA and RSSI methods are used for positioning, then implementation is simpler, but security against phase manipulation attacks deteriorates
Solution Approach 1:
The patent applies preliminary anti-action by transmitting adjacent channel signals before and during the main ranging signal transmission. These adjacent signals preemptively counter potential phase manipulation and symbol level attacks by creating detectable interference patterns that reveal tampering attempts, thereby securing the positioning measurement against security threats
Solution Approach 2:
The adjacent channel signals act as an intermediary security layer between the main ranging signal and potential attackers. By introducing these intermediate signals on nearby frequencies, the system creates a protective field that detects and mitigates phase roll-over and symbol level attacks without interfering with the primary positioning function
3Reliability
If multiple chipsets are deployed for sensing and adjacent signal transmission, then positioning security is improved, but cost increases
Solution Approach 1:
The patent combines multiple functions into a single supporting chipset, reducing the total number of chipsets required in the system. This merging approach maintains security through the same adjacent signal transmission capability while lowering component count, manufacturing complexity, and overall cost
Data Source
AI summary
Disclosed are techniques for time-multiplexing between sensing and adjacent signal transmission functionalities on the same hardware platform, such as a chipset supporting a main ranging device in passive entry passive start (PEPS) applications using secure multi-carrier phase-based ranging solutions to estimate the range between the main ranging device and a target device. The supporting chipset may be configured to operate as a sensor to receive continuous tone (CT) signals or round-trip time (RTT) packets exchanged between the main ranging device and the target device in a timeslot of a ranging cycle to improve the accuracy of the range estimates. In a different timeslot, the supporting device may operate as a transmitter to transmit CT signals or RTT packet on a channel adjacent to the channel used by the main ranging device to protect the CT signals or the RTT packets transmitted from the main ranging device against symbol level attacks.