A communication device selects a frequency bandwidth via which a physical layer (PHY) protocol data unit (PPDU) will be transmitted in a vehicular communication network, and generates, the PPDU i) according to a downclocking ratio of 1/2, and ii) based on an orthogonal frequency division multiplexing (OFDM) numerology defined by an IEEE 802.11ac Standard. In response to the selected frequency bandwidth being 10 MHz, the PPDU is generated according to the downclocking ratio of 1/2 and based on the OFDM numerology defined by the IEEE 802.11ac Standard for 20 MHz PPDUs. In response to the selected frequency bandwidth being 20 MHz, the PPDU is generated according to the downclocking ratio of 1/2 and based on the OFDM numerology defined by the IEEE 802.11ac Standard for 40 MHz PPDUs.