A controller is configured to control the adaptive notch filter and to execute a search technique (e.g., artificial intelligence (AI) search technique) to converge on filter coefficients and to recursively adjust the filter coefficients of the adaptive notch filter in real time to adaptively adjust one or more filter characteristics (e.g., maximum notch depth or attenuation, bandwidth of notch, or general magnitude versus frequency response of notch).

A method is provided for acquiring a signal from a satellite in a global navigation satellite system. The signal includes a pseudorandom code. The method includes, for each time period of a plurality of time periods: generating samples of the signal, segments of the samples of the signal are correlated with a local copy of the pseudorandom code, thereby producing correlation values for the time period. A discrete Fourier transform is performed using, as inputs, the correlation values for the respective time period, thereby producing a frequency representation of the correlation values for the time period. The frequency representations of the correlation values for the plurality of time periods are combined according to a data hypothesis. When a magnitude of the combined frequency representations meets predefined criteria, a frequency corresponding to the magnitude is selected as a tracking frequency for the satellite.

GNSS receivers and systems within such receivers use improvements to reduce memory usage while providing sufficient processing resources to receive and acquire and track E5 band GNSS signals directly (without attempting in one embodiment to receive L1 GNSS signals). Other aspects are also described.

An RF clocked device can include a signal processor operable to receive an RF signal having an RF signal frequency and output a clock signal having a clock frequency based on the RF signal frequency. The RF clocked device can also include a clock operable to receive, and operate, using the clock signal. The clock can output at least one of a time and a date. In addition, a clock system can include an RF clocked device. The RF clocked device can include a signal processor operable to receive an RF signal having an RF signal frequency and output a clock signal having a clock frequency based on the RF signal frequency. The RF clocked device can also include a clock operable to receive, and operate, using the clock signal. The clock can output at least one of a time and a date. The clock system can also include a client device operable to receive timing information from the RF clocked device.

A controller is configured to control the adaptive notch filter and to execute a search technique (e.g., artificial intelligence (AI) search technique) to converge on filter coefficients and to recursively adjust the filter coefficients of the adaptive notch filter in real time to adaptively adjust one or more filter characteristics (e.g., maximum notch depth or attenuation, bandwidth of notch, or general magnitude versus frequency response of notch).

GNSS receivers and systems within such receivers use improvements to reduce memory usage while providing sufficient processing resources to receive and acquire and track E5 band GNSS signals directly (without attempting in one embodiment to receive L1 GNSS signals). Other aspects are also described.

An electronic control unit comprises circuitry to receive a combined signal via a vehicle bus of a vehicle, wherein the combined signal contains a combination of a data signal and a watermark signal, which can be a radio frequency (RF) signal or an analog baseband signal, wherein the data signal includes a message, circuitry to extract a watermark from the watermark signal, circuitry to verify the watermark based on a comparison of the watermark with a pre-defined watermark, circuitry to extract the data signal from the combined signal and obtain the message from the data signal, and circuitry to authenticate the message based on the verification of the watermark.

GNSS receivers and systems within such receivers use improvements to reduce memory usage while providing sufficient processing resources to receive and acquire and track E5 band GNSS signals directly (without attempting in one embodiment to receive L1 GNSS signals). Other aspects are also described.

A method and apparatus detects and estimates geo-observables of navigation signals employing civil formats with repeating baseband signal components, i.e., “pilot signals,” including true GNSS signals generated by satellite vehicles (SV’s) or ground beacons (pseudolites), and malicious GNSS signals, e.g., spoofers and repeaters. Multi-subband symbol-rate synchronous channelization can exploit the full substantive bandwidth of the GNSS signals with managed complexity in each subband. Spatial/polarization receivers can be provided to remove interference and geolocate non-GNSS jamming sources, as well as targeted GNSS spoofers that emulate GNSS signals. This can provide time-to-first-fix (TTFF) over much smaller time intervals than existing GNSS methods; can operate in the presence of signals with much wider disparity in received power than existing techniques; and can operate in the presence of arbitrary multipath

A controller is configured to control the adaptive notch filter and to execute a search technique (e.g., artificial intelligence (AI) search technique) to converge on filter coefficients and to recursively adjust the filter coefficients of the adaptive notch filter in real time to adaptively adjust one or more filter characteristics (e.g., maximum notch depth or attenuation, bandwidth of notch, or general magnitude versus frequency response of notch).