Preamble structure supporting full duplex communications

A method at a network node that is configured to simultaneously transmit and receive wireless RF signals, the method comprising:

• transmitting, from the network node, a downlink message having a preamble that includes channel estimation information followed by a data portion;
• monitoring, at the network node, a frequency channel for the channel estimation information included in the downlink message, and prior to transmitting the data portion of the downlink message, estimating and cancelling a self-interference channel in the frequency channel based on the monitored channel estimation information;
• and
• receiving, at the network node, an uplink message in the frequency channel during a time period that overlaps with transmitting the data portion of the downlink message,
• wherein auto-detection information is included in the preamble of the downlink message, and theauto-detection information in the preamble comprises information encoded using a different modulation than other information in the preamble.