A null steering adjuster in a stationary wireless network identifies the presence or absence of a current set of phase differences in a dataset. The dataset includes legitimate sets of phase differences detected between radio frequency signals received by multiple antennas from respective legitimate sources. The current set of phase differences is detected between radio frequency signals currently received by the antennas. When the current set of phase differences is absent from the dataset, a null is created in the antenna pattern of the antennas in the direction of the currently-received radio frequency signals. When the current set of phase differences is present in the dataset, the antenna pattern is maintained.

A power line interference (PLI) suppression method includes receiving an input analog signal superimposed with PLI, and digitally estimating one or more harmonics of the PLI in real-time. Responsively to the one or more digitally estimated harmonics, one or more analog harmonic waveforms are outputted, that match the respective one or more harmonics of the PLI. The input analog signal and the one or more analog harmonic waveforms are received, and the superimposed PLI in the input analog signal is suppressed using the one or more analog harmonic waveforms. An analog output signal is outputted, that corresponds to the input analog signal having the suppressed PLI.