Phone as a key low latency vehicle access

Abstract

A Phone-as-a-Key (PaaK) system includes a pre-processor, a secure processor disposed in communication with the pre-processor, a cache memory associated with the pre-processor and the secure processor, and a memory for storing executable instructions. The pre-processor and the secured processor are configured to perform steps that can mitigate delay caused by mobile device authentication. For example, the pre-processor authenticates an authentication message associated with a mobile device used as a key for the vehicle, and stores the message in the cache memory. The pre-processor receives a door latch actuation signal, and initializes the secure processor in response. The pre-processor then provides access to the vehicle based on the secure processor initialization instruction, and the authentication message stored in the cache memory. After initialization, the secure processor sends a challenge value for second authorization of the mobile device, and triggers remedial actions if the device fails to respond correctly.