Patent Document ID: 9768894
Application ID: 14822177
Patent Flag: 1

Claim One:
1. A system for identifying radio frequency (RF) transmitters in an environment, the system comprising: at least one RF listening station configured to receive RF signals and acquire measurements of their RF power as a function of reception time, t, and frequency f; and a processing hub configured to identify RF transmitters operating in the environment by: receiving the RF power measurements; fitting to the RF power measurements a probability mixture model (PMM) that provides a probability density as a function of magnitude of the RF power measurements, the PMM comprising a plurality of probability density functions (PDFs), at least two of which PDFs are of a different type, the fitting comprising: determining a set of defining parameters θ PMM for the PMM, the defining parameters comprising a number, “K”, for a number of the plurality of PDFs, and for each PDF, parameters defining the PDFs; and, iteratively partitioning the RF power measurements into a plurality of sub-blocks of power measurements; for each given sub-block in an i-th iteration fitting a sub-block PMM comprising a plurality of sub-block PDFs to the RF power measurements in the given sub-block independent of RF power measurements in other sub-blocks of the i-th iteration to determine a set of defining parameters for the sub-block PMM, the set of defining parameters for the sub-block PMM having a number for the plurality of PDFs in the sub-block PMM; clustering sub-block PDFs from different sub-blocks to determine clusters of PDFs; and determining K responsive to a number of clusters; and, identifying RF transmitters in the environment responsive to the PMM.