Systems, methods, and apparatuses for detecting interference caused by a wireless local area network (WLAN) and a wireless wide area network (WWAN) node operating in an unlicensed or shared spectrum is disclosed. In accordance with the present disclosure, a base station may generate a null tone pattern for one or more subframes transmitted to the UE. The null tone pattern may include one or more null tones mapped to consecutive symbols in each resource block to detect interference. Accordingly, a UE may monitor a wireless channel from a base station for a null tone transmission. The UE may detect a null tone pattern by decoding a known physical layer channel to identify the null tone pattern. In some aspects, the UE may generate channel estimates, decode allocated resources, determine timing of future transmissions and/or establish communication with the base station based on the identified null tone pattern.