A method of wireless communication, executed by a user equipment (UE), receives, from a base station, a broadcast or multicast message including a known payload, as well as a configuration for the known payload. The method also trains an artificial neural network with the known payload. A method of wireless communication, executed by a base station, configures a known payload for multiple UEs and signals, to the UEs, an indication of which physical channel will include the known payload, as well as time/frequency resources of the known payload. The method also broadcasts or multicasts the known payload to facilitate neural network training at the UEs.