Protected, low-power vehicle-access by smart keys and wearables

November 14, 2016 // By Graham Prophet
Microchip has announced, primarily for the automotive sector, a passive entry/passive start (PEPS) system that it believes to be the lowest-power available. The ATA5700 and ATA5702 are intended for use in battery powered applications such as smart keys (i.e. PEPS) and complementary car access via mobile devices, smartphones and wearables where the power consumption is one of the key requirements.

The chip pair features an open immobilizer protocol for interoperability; low-frequency vector techniques enhance man-in-the-middle counterattack strategies; devices offer ultra-low power consumption with three times longer battery life than alternative products; and maximise key localization accuracy.

 

Vehicle theft based on relay attacks of vehicles equipped with a PEPS system is becoming one of the top security concerns of carmakers. These two devices have a built-in Low Frequency (LF) vector calculation unit that allows customers to implement effective relay attack countermeasures at no additional cost. That is, they establish that not only are the correct credentials being presented by the ‘key’ but that the key – or other authorised device – is in fact in proximity to the vehicle (close by to gain access/within the vehicle to start.

 

The new devices also feature low frequency sensitivity, enabling convenience features such as customized welcome-lighting upon approaching the vehicle or automatic “walk-away locking” of the vehicle – in a range up to 10 metres. The power consumption for this “always on feature” triples battery lifetime in the highest sensitivity mode. The devices offer the highest key localization accuracy in the market which is critical to accurately distinguish whether a key fob is located inside or outside the vehicle and to comply with accuracy requirements of insurance companies. In addition, the devices contain an open-source, zero-cost license immobilizer protocol based on AES-128 [encryption] that enables interoperability, allowing large volume customers to deploy second sourcing strategies.

 

Both ATA5700 and ATA5702 feature a 3D immobilizer, 3D high sensitivity LF receivers, digital processing unit, 128-bit crypto engine, LF vector calculation unit and a microcontroller. The ATA5702 is enhanced with a built-in RF transmitter fractional phase-locked loop (PLL) to ensure a robust ultra-high frequency (UHF) link that is highly immune to jammers and disturbers. The ATAK51004-v2 evaluation kit supports product evaluation.

 

Microchip; www.atmel.com/devices/ATA5700.aspx