Project

Passive Keyless Entry System

Application

Vehicle Electronics

Customer Need

A Tier1 automotive company desired a fully functional, production-ready design of a passive keyless entry and ignition system to offer to major automotive OEMs. The system uses low frequency immobilizer technology leveraging RFID techniques. System components include base station, key fob, and highly directional antennas. A system prototype integrated into an actual vehicle for presentation purposes is included in the development program.

AVID's Solution

Using technology and components which are targeted for RKE and RFID, AVID designed the base station and key fob boards. HF was used for traditional push button operation, whereas LF was used to achieve the passive hands-free mode. Multiple antennas are required to accurately detect the position of the fob; inside or outside the vehicle. This allows starting when inside the passenger compartment, but inhibited when outside. Additionally, a locked door will remain locked when the fob is inside, but unlocks when in close proximity outside. Custom omni-directional antennas to facilitate LF and HF wavelengths were designed to fit in side view mirrors, door handles, and in the passenger compartment. A custom electro-mechanical latch was designed to address combo electro-mechanical and straight mechanical opening and locking. Rolling code algorithms were implemented for security. The fob required special attention to power management to achieve long battery life. Critical factors considered for the design include automotive environmental and EMC requirements, cost, reliability, safety, and adaptability to different vehicles.

Value Added or Technologies Applied

• Product Specification
• System Architecture and Design (Hardware, Firmware, Mechanical, RF)
• Prototype and Validation
• Multiple Demonstration System Integrations (Vehicle Cut-Away, Full Vehicle, Motorcycle, Bench Top Demo System)
• Project Management of Several Third Party Contributors of System Components
• Manufacturing Engineering Support, Production Test Procedure
• Customer Support for OEM Presentations and SAE Show Support for Demo Platforms and Booth Duty