Methods, systems, and devices for wireless communications are described. Some systems may support digital post-distortion (DPoD) processing at a base station. In some such systems, a user equipment (UE) may process a data message for transmission, where a resulting signal associated with the data message includes non-linear characteristics that are handled by DPoD on the receiver-side. The non-linear characteristics may cause the signal to leak into out-of-band (OOB) resources, potentially resulting in interference. In some examples, the UE may transmit the data message to the base station in a multi-user system. To support mitigation of non-linear interference on signaling by other UEs, the UE may additionally transmit pilot signals in OOB resources (e.g., in addition to in-band resources) where the non-linearity may be expected to negatively affect other communications. The base station may use the OOB pilot signals to perform channel estimation and interference mitigation.