Padding and backoff operations when transmitting via multiple frequency segments in a wlan

A communication device, comprising:

• a wireless network interface device that is configured to communicate via multiple frequency segments, the wireless network interface device including one or more integrated circuit (IC) devices and a plurality backoff counters implemented on the one or more IC devices, wherein the one or more IC devices are configured to:
• determine that the communication device is to transmit in a first frequency segment simultaneously with transmitting in a second frequency segment,
• perform a first backoff operation with a first backoff counter among the plurality of backoff counters to determine when to transmit a first packet in the first frequency segment, the first backoff counter measuring a first contention window,
• perform a second backoff operation with a second backoff counter among the plurality of backoff counters to determine when to transmit a second packet in the second frequency segment, the second backoff counter measuring a second contention window,
• in connection with the first backoff counter expiring, control the wireless network interface device to transmit the first packet in the first frequency segment,
• in connection with the second backoff counter expiring, control the wireless network interface device to transmit the second packet in the second frequency segment simultaneously with transmitting the first packet in the first frequency segment, and
• in response to determining that transmission of the first packet in the first frequency segment failed:
• increase the first contention window for a retransmission of the first packet in the first frequency segment, and
• not adjust the second contention window for a next transmission in the second frequency segment.