Implementation challenges of time synchronization in vehicular networks

Time synchronization has a paramount role in designing efficient Medium Access Control (MAC) in multi-channel wireless access in vehicular environment (WAVE). In short range communication in WAVE, every On-board unit (OBU) and every roadside unit (RSU) have to concord with message exchanges within control channel (CCH) intervals and service channel (SCH) intervals. Timestamp synchronization has to be done within high priority emergency message exchanges (typically within CCH intervals and optionally within SCH intervals) or non-safety message exchanges (typically within SCH intervals). The short ranged WAVE devices need to harmonize among each other through exchange of Timing Advertisement (TA) frames within the coverage region. In this paper, we propose an efficient WAVE MAC implementation to communicate high priority control information such as exchanging TA frames. These TA messages play extremely important role in time synchronization for reliable inter-vehicular environment. We have explored the synchronization of CCHs and SCHs in the 75 MHz allocation (5.850 GHz to 5.925 GHz) in 5.9 GHz band WAVE system and this method effectively deals with timeline alignment and channel switching for various channel access modes (continuous, alternating, immediate and extended) specified in IEEE 1609.4 and IEEE 802.11p WAVE MAC protocol.

[1]  Chai-Keong Toh,et al.  F-PCM: a fragmentation-based power control MAC protocol for IEEE 802.11 mobile ad hoc networks: Research Articles , 2006 .

[2]  A. Föhrenbach,et al.  SIMPLE++ , 2000, OR Spectr..

[3]  Deborah Estrin,et al.  Proceedings of the 5th Symposium on Operating Systems Design and Implementation Fine-grained Network Time Synchronization Using Reference Broadcasts , 2022 .

[4]  Dirk Pesch,et al.  A network centric simulation environment for CALM-based cooperative vehicular systems , 2010, SimuTools.

[5]  James M. Conrad,et al.  Time synchronization in wireless sensor networks: A survey , 2010, Proceedings of the IEEE SoutheastCon 2010 (SoutheastCon).

[6]  Frank Adelstein,et al.  Fundamentals of Mobile and Pervasive Computing , 2004 .

[7]  Giovanni Pau,et al.  TimeRemap: stable and accurate time in vehicular networks , 2010, IEEE Communications Magazine.

[8]  Weiwei Xia,et al.  An Adaptive Multi-Channel MAC Protocol with Dynamic Interval Division in Vehicular Environment , 2009, 2009 First International Conference on Information Science and Engineering.

[9]  Qun Li,et al.  Global clock synchronization in sensor networks , 2006, IEEE Transactions on Computers.

[10]  Yi Yang,et al.  Evaluation of VANET-based advanced intelligent transportation systems , 2009, VANET '09.

[11]  Yingyu Wan,et al.  Accurate Time Synchronization for Wireless Sensor Networks , 2005, MSN.

[12]  Luca Delgrossi,et al.  IEEE 802.11p: Towards an International Standard for Wireless Access in Vehicular Environments , 2008, VTC Spring 2008 - IEEE Vehicular Technology Conference.

[13]  D. P. Bovet,et al.  Operating System ’ s Support for Multicore Systems : Current and Future Trends 24 / 04 / 2007 , 2007 .

[14]  Mihail L. Sichitiu,et al.  Simple, accurate time synchronization for wireless sensor networks , 2003, 2003 IEEE Wireless Communications and Networking, 2003. WCNC 2003..

[15]  Saurabh Ganeriwal,et al.  Timing-sync protocol for sensor networks , 2003, SenSys '03.

[16]  Chai-Keong Toh,et al.  F-PCM: a fragmentation-based power control MAC protocol for IEEE 802.11 mobile ad hoc networks , 2006, Wirel. Commun. Mob. Comput..

[17]  Jinhui Xu,et al.  Towards a theory for securing time synchronization in wireless sensor networks , 2009, WiSec '09.

[18]  K. Yıldırım.  CLOCK SYNCHRONIZATION IN WIRELESS SENSOR NETWORKS , 2012 .

[19]  Ajay D. Kshemkalyani,et al.  Clock synchronization for wireless sensor networks: a survey , 2005, Ad Hoc Networks.

[20]  Ahmad Khademzadeh,et al.  VWCA: An efficient clustering algorithm in vehicular ad hoc networks , 2011, J. Netw. Comput. Appl..

[21]  Raja Sengupta,et al.  Vehicle-to-vehicle safety messaging in DSRC , 2004, VANET '04.