The disclosure provides some embodiments for securing long training field (LTF) sequence. A responding station (RSTA) configures a location management report (LMR) frame. The LMR frame is configured to include an LMR in respect of a previous measurement, and data to be used to generate a null data packet (NDP) for a current measurement that is to be performed following the previous measurement. The RSTA further encrypts the LMR frame using protected management frames (PMF) scheme, and transmits the encrypted LMR frame to an initiating station (ISTA) for generating an LTF sequence for the current measurement. In response to receiving an NDP announcement (NDPA) and an NDP for the current measurement from the ISTA, the RSTA generates an NDP for the current measurement based on the NDPA and the data using CCMP, and transmits the NDP to the ISTA.