IEEE 1609.x V2X On-Board-Unit (OBU)

-A A +A

The OBU-201U contains V2X OBU elements of DSRC/GNSS/HSM with pre-integrated IEEE 802.11p driver and IEEE 1609.x protocol stacksrunning on ThreadX RTOS. Programmers can directly deployed V2X application programs on OBU-201U through SDK and protocol stack API.

Automotive-grade design ensures vibrational and environmental reliability. Interoperable and standard compliant IEEE 1609.x protocol stacks ensure the best performance and compatibility with all OBUs and RSUs.

OBU-201U is a V2X-ready OBU solution for trials or retrofit deployments, also, can painlessly enable V2X on existing Wi-Fi outdoor Access Point through Ethernet port connection and Unex’s unique OSLink/SDK.

  • V2X OBU solution for trials or retrofit deployment: contains RF, modem, security, positioning, IEEE 802.11p driver, 1609.x protocol stacks, and SDK (including tool-chain, protocol stack API, and user guide)  for V2X programs deployment.
  • Flexibility to connect OBU-201U to existing outdoor Wi-Fi access point through Ethernet port and painlessly enable V2X on the access point through Unex’s unique OSLink and SDK.
  • Complete 1609.x V2X protocol stacks: contains IEEE 1609.2, 1609.3, 1609.4 and SAE J2735 stacks.
  • More than +20dBm Class C RF spectrum mask compliant with margins.  
  • Superior fading sensitivity in the typical ETSI defined C2C multipath scenarios increases wireless coverage.
  • Internal 40MHz BW filter provide robust out-of-band radio interferences in multi-channel operation.
  • ECDSA256 accelerator provides line-rate verification to assure fixed and short latency.
  • Integrated Hardware Security Module (HSM) with dedicated V2X firmware enables ECDSA256 secure signing and ensures private keys are stored in a tamper proof device.
  • Dual PHY and MAC support concurrent dual channel operation.
  • High-performance GNSS receiver provides accurate positioning at 10Hz refresh rate. Optional Autotalks low latency algorithm reduces positioning latency which is essential for tracking in high mobility vehicles and future autonomous vehicles.
  • On board DIP switch for solo GNSS module test or firmware upgrade through DB9 RS232 interface.
  • Optimized system integration provides the longest communication range at high speed, even in the presence of obstructions.
  • AEC-Q100 qualified Autotalks V2X chipset (Q1/2015), 4-corner UV cured resin for BGA chips, and automotive-grade -40ºC ~ +85°C components (excluding Infineon -20°C ~ +85°C SLE97) ensure vibrational and environmental reliability.
  • Extensive connectivity in small 121x104.4mm PCBA size provides the most flexible integration options: one 10/100Mbps Ethernet port, two CAN ports, one RS232 console, one audio jack, one on-board microSD socket, and on-board 8-pin GPIO.
  • 128MB DDR3 and 32MB Nor Flash system memory.
  • microSD socket to use flash memory for logging purpose. 
  • On Board programmable delay ON circuitry (default 200ms) for cracking delay function.
  • Dual DC 9-32V power inputs:

one separated 4-pin automotive power connector supporting ACC and Vbatt. Vbatt supports power supply to GNSS module RTC for hot start. 

the other DC power round jack for laboratory application development.

  • 40V 3000W passive TVS and active IC LTC4365 and 80V dual MOS ensure robust UV/OV/RV protection on ACC trail.
  • 40V 3000W passive TVS on Vbatt trial to LT3014 to GNSS VRTC circuitry provides GNSS hot start power trial protection.
  • Two Fakra type Z DSRC connectors support receiver diversity and enable robust assembly in automotive environment.
  • One Fakra type C GPS connector for automotive application.
  • High ESD protection circuit and ESD ground cable design ensure immunity and robustness of antenna and CAN ports in ESD events.
  • EMI and power filter design effectively reduce power noise.
  • RoHS compliance meets environment-friendly requirements.
Software Specifications
Operation System ThreadX RTOS
Standard Compliance

IEEE 802.11p, IEEE 1609.2, IEEE 1609.3, IEEE 1609.4, SAE J2735

(Remark: update firmware will be provided after new standard finalized by project request)

Frequency Range

5.85 ~ 5.925GHz

(Remark: DSRC messages over 5.15 ~ 5.925 full band will be supported by project base.)

Protocol Stack

pre-integrated IEEE 1609.x protocol stacks:

  • IEEE 1609.2 - 2013
  • IEEE 1609.3 – 2010
  • IEEE 1609.4 – 2010
  • SAE J2735 Version 2
  • IEEE 1609.11 - Standard for Electronic Toll Collection by project base

172, 174, 176, 178, 180, 182, 184 (5.9GHz DSRC)

( Remark: DSRC messages over 5.15 ~ 5.925 full band will be supported by project base.)

SDK tool-chain, protocol stack API, and user guide
Hardware Specifications
Main Chipset
  • Autotalks CRATON (ATK4100) V2X communication processor: 3-core (one ARM Cortex R4F and two Synopsys ARC 625D) running at 240MHz
  • Autotalks PLUTON (ATK3100) V2X RF Transceiver
  • Telit SL869 GNSS module
  • Infineon SLE97 Hardware Security Module (HSM)

32MB NOR system memory and 128MB DDR3 storage memory

  • one DSRC radio
  • frequency band: 5.85 – 5.925GHz (ITS-DSRC)
  • radio mode: 802.11p
  • operation mode: WAVE, Ad-hoc (TBC), Infrastructure (TBC) 
  • RF transmit power:  > +20 dBm Class C RF spectrum mask compliant with margins.
  • fading Sensitivity    Power @ 10% PER sensitivity (6Mbps, 1000B packet), fading channels as 5 typical C2C multipath scenarios defined by ETSI: ± 2dBm
    • Rural LOS: -92.5dBm
    • Highway LOS: -91.5dBm
    • Urban Approaching LOS: -91.5dBm
    • Crossing NLOS: -89.5dBm
    • Highway NLOS: -88.5dBm
  • receiver sensitivity: typical -90 dBm (TBC)
  • DSRC antenna: two 5.9 GHz Fakra type Z antennas (TBC) 
  • one GPS radio
  • refresh rate:10Hz
  • accuracy: TBC
  • GPS antenna: one active Fakra type C antenna (TBC)
Security ECDSA verification, ECIES encryption, HSM security signing and storing
  • two DB-9 female CAN 2.0 ports
  • one 10/100Mbps Ethernet port
  • one DB-9 male RS232 console port
  • one audio jack
  • one switch button
  • one on-board microSD socket for flash memory
  • two Fakra type Z DSRC connectors
  • one Fakra type C GPS connector 
Power Supply

dual DC 9-32V power inputs:

  • one 4-pin power connector supporting Vbatt. (Power-In) and ACC;
  • one DC power round jack
Operation Voltage DC 9 ~ 32 V ± 5%
Operation Temperature Range ambient: -40ºC ~ +85ºC (Infineon SLE97 Hardware Security Module supports -20ºC ~ +85ºC , will change to SLI97 on H2/2015 production to support -40ºC ~ +85ºC) 
Operating Humidity 10% ~ 95%, non-condensing
Storage Humidity max. 95%, non-condensing
Environment-Friendly Compliance RoHS
Dimension PCBA size: 121 mm(L) x 104.4mm(W)