New to Newark/element14? Start here
2013/05/24
 
 
 
Electronic Applications

APPLICATIONS

All the resources you need to bring your designs to life

Back to: Applications > Wireless > Car Access System

Applications Home

Industrial Automation

Lighting

Alternative Energy

Wireless

Products

Solutions

Design Resources

Sensing

Robotics

Medical

Car Access System

Access System diagram

Car Access System is a system designed to permit or deny access to premises. Early car access systems were based on purely mechanical structures designed only for anti-theft function. After then benefited from microelectronic and RF technologies, they have improved security functions and featured new capabilities such as automatic vehicle tracking and window roll-up/down. Currently, the technologies most widely and successfully applied in these systems are RKE and PKE. RKE (Remote Keyless Entry) controls car doors and trunk lids by sending wireless signal when users press the buttons on keyfobs. While PKE (Passive Keyless Entry), which can be regarded as advanced RKE, allows users open car doors just by directly pulling door handles without the need to press any button.



[+MORE]

A typical RKE system has a wireless transmitter (operating at 315 MHz or 433.92 MHz), a MCU embedded in the car keys to realize control over cars. The MCU mostly stays in sleep mode in order to save power. When a button on car keys is pressed, MCU wakes up and controls transmitter to send out a 64-bit or 128-bit data stream after carrier modulation. The data is received by a RF receiver installed in cars and passed on to another MCU which verifies sender’s identity and gives instructions to control mechanism to open doors. The keyfobs with multiple buttons can provide several other functions such as opening trunks and starting engine.


Comparing with RKE systems, PKE has an additional pair of low-frequency (125 KHz) transmitter and receiver which are installed respectively in cars and keyfobs. When users carrying a PKE key pull a door handle of a car, the low-frequency transmitter in car is activated instantly and sends out a signal. The receiver embedded in keyfob receives that signal with a 3-dimentional antenna and makes a comparison between the signal and its stored data. If they match, the key is awaked and sends a high-frequency (315 MHz or 433.92 MHz) signal back to the car. And if this signal is found valid, car doors will be unlocked immediately. The whole procedure only takes several milliseconds so that users will not perceive even a slight delay. Additionally, PKE can provide a good anti-theft performance by, for example, automatic locking doors, closing windows, cutting off fuel supply and power source when users carrying the key are more than 3-5 meters away from cars. [-LESS]


Hover over the diagram blocks to view more recommended solutions.

Low power MCU for RKE or PKE.Some MCU integrate with UHF Transmitter or LF 3D analog front end.
Click for full parts list

Low cost automotive MCU with CAN/LIN.
Click for full parts list

315MHz or 433.92MHz UHF transmitter IC or module.

ADF7012BRUZ
ADF7012BRUZ
Analog Devices
NRF9E5
NRF9E5
Nordic
Semiconductor

Click for full parts list

315MHz or 433.92MHz UHF transmitter IC or module.

ADF7012BRUZ
ADF7012BRUZ
Analog Devices
NRF9E5
NRF9E5
Nordic
Semiconductor

Click for full parts list

Encryption KEELOQ encoder for RKE or PKE.

HT12E-20SOP
HCS301-I/SN
HCS301-I/SN
Microchip
HT12E
HT12E
Holtek

Click for full parts list

Encryption KEELOQ decoder for RKE or PKE.

HT12D
HT12D
Holtek
HT12D-20SOPLF

Click for full parts list

Keyfod for RKE.
Click for full parts list

Automotive Class CAN/LIN Transceiver

MCP2551-I/SN
MCP2551-I/SN
Microchip

Click for full parts list


 
RX2A-433-64
RX2A-433-64
RADIOMETRIX
The TX2H/RX2A are 433/434MHz single-channel FM transmitter/receiver modules, capable of handling raw data rates up to 64kb/s with usable range of 500m. The Transmitter uses PLL locked to a crystal for frequency stability over a wider temperature range. The TX2A and RX2A modules will suit one-to-one and multi-node wireless links in applications including car and building security, EPOS and inventory tracking, remote industrial process monitoring and computer networking.
1439949
 
MCP2515DM-BM
MCP2515DM-BM
Microchip
The MCP2515 CAN Bus Monitor Demo kit contains two boards that connect together to create a simple two node Controller Area Network (CAN) bus, which can be controlled and/or monitored via PC interface that users configure the MCP2515 registers with, and send/receive CAN messages. The board(s) can also be connected to an existing CAN bus.
1439949
 
32000467
32000467
MIPOT
The 3-2000467 module is an On-Off Key transceiver operating at 433,92 MHz, with typical transmission output power of 10 mW (+10 dBm) and the receiver sensitivity reaching –100 dBm, with auxiliary pin for RF input/output to limit the current consumption.
1439949
 
RCR-433-EPR
RCR-433-EPR
RADIOTRONIX
The RCR-XXX-EPR module receives On-off keyed (OOK) modulation signal and demodulated to digital signal for the next decoder stage. Local Oscillator is made of L/C structure. The module is designed specifically for unlicensed remote control and wireless security receiver operating at 315/433 MHz.
1439949
 
RDF1-433
RDF1-433
RF SOLUTIONS
The RDF1 is an FM receiver/decoder module, providing a radio system with up to four digital outputs and single serial data output when used with an RF Solutions FIREFLY or HORNET series Handheld transmitters. A system using the RDF1 can achieve up to 200m range, depending on transmission conditions.
The RDF1 consists of a front end super-heterodyne receiver and an embedded microcontroller which decodes the RF string for a compatible transmitter and outputs to 4 telemetry lines and as serial data, capable of 200m range, dependant upon transmission conditions
1439949
 
MCP2515DM-PCTL
MCP2515DM-PCTL
Microchip
The MCP2515 PICtail™ Demo Board implements a simple CAN bus with two nodes; node one uses the MCP2515 Stand Alone CAN controller, node 2 uses the MCP25020 CAN I/O Expander, each utilizing one input (push button) and one output (LED). The MCP2515 node transmits its input (push button) information at regular intervals and request input (push button) information from the MCP25020 at regular intervals. An LED on each node indicates the state of the other node's push button.
1439949
 
DM163015
DM163015
Microchip
The PICDEM CAN-LIN 3 Board demonstrates features of the PIC18F6680 and PIC18F8680 devices, including those of the integrated CAN module. Additionally, the board employs a LIN sub-network using PIC18F1320 and MCP201 LIN Bus.
1439949
 
Image Description  
MICROCHIP Encoder Secure Learning RKE Systems Using KEELOQ® Encoders HCSxxx Click here
MICROCHIP Encoder Programming KEELOQ® Devices with the PRO MATE® II Device Programmer HCSxxx Click here
MICROCHIP RF rfRXD0420 Receiver Module rfRXD0420 Click here
MICROCHIP RF rfRXD0420 ASK Receiver Reference Design rfRXD0420 Click here
MICROCHIP RF Designing an FCC Approved ASK rfPIC™ Transmitter  AN242  rfPIC Click here
MICROCHIP MCU Passive Keyless Entry (PKE) Reference Design PIC16F639 Click here
MICROCHIP MCU PKE System Design Using the PIC16F639 PIC16F639 Click here
FREESCALE SEMICONDUCTOR  MCU Remote Keyless Entry (RKE) Reference Design Using the  MC68HC908RF2 MC68HC908RF2 Click here
FREESCALE SEMICONDUCTOR  MCU Interfacing the MC68HC908QF4 Evaluation Board to RD68HC908RKE MC68HC908QF4 Click here
FREESCALE SEMICONDUCTOR  MCU Freescale Variable Key Security Protocol Transmitter User’s Guide Click here
TEXAS INSTRUMENTS  RF CC1000/CC1050 used with On-Off Keying  AN016 CC1000/CC1050 Click here
Manufacturer Product Type AN Title AN Number Part Number URL
INFINEON MCU PMAx1xx - Application Whitepaper Click here
INFINEON RF Application Whitepaper - RF or Infrared Click here
Manufacturer Product Type White Paper Title URL
MICROCHIP RF TRANSMITTER MODULE, RFPIC KIT, 433MHZ AC164101  rfPIC12F675F Click here
MICROCHIP RF TRANSMITTER MODULE, RFPIC KIT, 315MHZ AC164102 rfPIC12F675K Click here
MICROCHIP RF RECEIVER MODULE, RFPIC KIT, 433MHZ  AC164103 rfRXD0420/0920  Click here
MICROCHIP RF RECEIVER MODULE, RFPIC KIT, 315MHZ AC164104 rfRXD0420/0920  Click here
MICROCHIP RF KEELOQ® 3 Development Kit DM303007 PIC16F636  Click here
MICROCHIP MCU PIC16F639 Header Board AC162066 PIC16F639 Click here
MICREL SEMICONDUCTOR  RF RadioWire® 410 to 450MHz FSK Transceiver Development System MICRF506DEV1 MICRF506 Click here
MICREL SEMICONDUCTOR  RF RadioWire® 410 to 450MHz FSK Transceiver Development System MICRF620DEV1 MICRF506 Click here
Manufacturer Product Type Evaluation Kits Title EVKs Part Number Part Number URL
FREESCALE SEMICONDUCTOR  MCU S08SF 8 Bit Microcontrollers and Development Kits MC9S08 Click here
INFINEON MCU PMA71xx- SmartLEWIS™ MCUs PMA71xx Click here
MICROCHIP Interface MCP2515: Stand-Alone CAN Controller MCP2515 Click here
MICROCHIP MCU 8-Bit CMOS Microcontrollers With nanoWatt Technology Click here
Manufacturer Product Type Training Title Part Number URL
This is tab 6