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arXiv · 1905.05431

A TDMA-like Access Scheme with Splitting Request and Transmission for Vehicular Networks

Shenglong Peng·Xuan He·Junyi Du·Yong Liang Guan·Liang Zhou
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Abstract

In this paper, we consider safety message transmission in a dense vehicular network. With increasing vehicular network density, the collision rate increases when multiple vehicles transmit safety messages simultaneously. To address this issue, we propose a request-transmission split time division multiple access (TDMA) scheme, referred to as RTS-TDMA. In our scheme, we divide a frame into three phases, i.e., a contention access phase, a broadcast feedback phase, and a contention-free transmission phase. Each vehicle selects a repetition rate according to a given probability distribution and repeats the transmission of its request packet to improve the reliability of the request. In addition, a roadside unit acts as the coordinator and uses a successive interference cancellation technique to resolve request collisions. RTS-TDMA also reduces the request time percentage by containing only the vehicle identity in each request packet. Both theoretical analysis and numerical results verify that the RTS-TDMA scheme can provide higher throughput than the coded slotted ALOHA scheme.

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Shenglong Peng, Xuan He, Junyi Du, Yong Liang Guan, Liang Zhou. 2019-05-14. A TDMA-like Access Scheme with Splitting Request and Transmission for Vehicular Networks. https://arxiv.org/abs/1905.05431

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