Poster Abstract: Hierarchical Subchannel Allocation for Mode-3 Vehicle-to-Vehicle Sidelink Communications

TL;DR

This paper proposes a hierarchical subchannel allocation method for Mode-3 V2V sidelink communications that accounts for time orthogonality constraints to prevent conflicts among vehicles within clusters.

Contribution

It introduces a novel resource allocation approach that incorporates time orthogonality constraints, addressing limitations of traditional graph matching methods in V2V communications.

Findings

The proposed method effectively prevents subchannel conflicts within vehicle clusters.

It improves resource allocation efficiency in Mode-3 V2V sidelink communications.

The approach handles overlapping clusters with conflicting subchannel assignments.

Abstract

In V2V Mode-3, eNodeBs assign subchannels to vehicles in order for them to periodically broadcast CAM messages \cite{b2}. A crucial aspect is to ensure that vehicles in the same cluster will broadcast in orthogonal time subchannels\footnote{A subchannel is a time-frequency resource chunk capable of sufficiently conveying a CAM message.} to avoid conflicts. In general, resource/subchannel allocation problems can be represented as weighted bipartite graphs. However, in this scenario there is an additional time orthogonality constraint which cannot be straightforwardly handled by conventional graph matching methods \cite{b3}. Thus, in our approach the mentioned constraint has been taken into account. We also perform the allocation task in a sequential manner based on the constrainedness of each cluster. To illustrate the gist of the problem, in Fig. 1 we show two partially overlapping clusters where a conflict between vehicles $V_8$ and $V_{10}$ is generated as the allotted subchannels are in the same subframe.