Performance of PHY/MAC Cross-Layer Design for Next-Generation V2X Applications

Abstract

This paper proposed the use of physical (PHY) and medium access control (MAC) cross-layer approach to obtain two goals outlined by the next-generation V2X (NGV) ’s project authorisation request (PAR) of IEEE 802.11bd group, namely having twice the MAC layer throughput and able to operate in a high mobility scenario of up to 500 km/h. At the PHY layer, we suggested utilising mid-ambles channel estimation (MCE), dual-carrier modulation (DCM), and multiple-input multiple-output space-time block coding (MIMO-STBC). At the MAC layer, we suggested an aggregate MAC protocol data unit (A-MPDU) aggregation technique, choosing an appropriate contention window (CW) value, and setting a limit for re-transmissions. We designed a model utilising a cross-layer approach then we simulated the performance of normalised system throughput for two types of V2X applications, namely safety-related (high reliability) and non-safety (high throughput) V2X applications. To better portray the high-mobility scenario, we used the enhanced highway line of sight (LOS) channel model. Our simulation results showed two times normalized throughput performance improvement for both V2X applications in a high mobility environment, as requested by the NGV standard’s PAR.