Mitigating Doppler effects on physical-layer network coding in VANET

Ling Fu Xie, Wang Hei Ho, Soung Chang Liew, Lu Lu, Chung Ming Lau

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review

5 Citations (Scopus)

Abstract

This paper considers physical-layer network coding (PNC) in vehicular ad-hoc network (VANET) to solve the problem of short contact time between fast-moving vehicles. PNC enables data exchange between nodes in a relay network within a short airtime, e.g., twice faster than relay networks based on traditional communication, and can be a powerful performance booster in VANET. One of the most important challenges in applying PNC to VANET, however, is the Doppler shift caused by vehicular motions. Doppler shift leads to carrier frequency offset (CFO) that induces inter-carrier interference (ICI) in OFDM systems. The ICI destroys the orthogonality of modulated symbols, causing degradation in PNC signal detection. This paper puts forth a detection method to mitigate the CFO/ICI effect on PNC. The method, referred to as BP-VPNC, makes use of a belief propagation (BP) algorithm to process the outputs of the OFDM correlators. BP extracts useful hidden information embedded in ICI to improve signal detection in VANET PNC. Our study shows that the BER performance of PNC VANET operated with BP-VPNC can be achieved close to that of traditional VANET at various CFO levels. These results suggest that with BP-VPNC, a potential shortcoming of PNC, vulnerability to CFO, can be circumvented, and that PNC can be used to overcome the short vehicular contact time in VANET.
Original languageEnglish
Title of host publication2015 IEEE 26th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications, PIMRC 2015
PublisherIEEE
Pages121-126
Number of pages6
Volume2015-December
ISBN (Electronic)9781467367820
DOIs
Publication statusPublished - 1 Dec 2015
Event26th IEEE Annual International Symposium on Personal, Indoor, and Mobile Radio Communications, PIMRC 2015 - Hong Kong, Hong Kong
Duration: 30 Aug 20152 Sep 2015

Conference

Conference26th IEEE Annual International Symposium on Personal, Indoor, and Mobile Radio Communications, PIMRC 2015
Country/TerritoryHong Kong
CityHong Kong
Period30/08/152/09/15

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

Cite this