H04K3/228

Algorithm and techniques for high-resolution interference parameter estimation in low-swap environment

Techniques for providing a multi-stage iterative scheme to determine fine granularity estimates of parameters of an interfering signal and for using the fine granularity estimates of the parameters to reduce an impact of the interfering signal against a signal of interest (SOI) are disclosed. An input signal is identified. A first set of estimation parameters that provide a coarse granularity estimate of a center frequency of the jamming signal and of a symbol rate of the jamming signal are determined. The first set of estimation parameters are refined to generate a medium granularity estimate of the center frequency and the symbol rate of the jamming frequency. The medium granularity estimates are also refined to produce a fine granularity estimate of the center frequency and the symbol rate. The fine granularity estimates are used to remove or reduce an influence of the jamming signal on the input signal.

COMPACT RECEIVER SYSTEM WITH ANTIJAM AND ANTISPOOF CAPABILITY
20220247510 · 2022-08-04 ·

A signal-of-interest is received by using a first and second planar electrically conductive disc to define an antenna. The antenna produces RF signal outputs at three output ports E.sub.x, E.sub.y and E.sub.z, each having a different associated gain pattern and polarization response. At least one null is automatically asserted in a pattern defined by the antenna in a specified direction by selectively weighting a gain and a phase of the RF signals respectively produced from the three output ports and then combining the RF signals to produce a first receiver signal output.

System and method for index modulation based joint mode frequency hopping with vortex electromagnetic waves for anti-jamming
11444654 · 2022-09-13 · ·

A system and method of index modulation based joint mode frequency hopping with vortex electromagnetic waves for anti-jamming are provided. The system is additionally provided with a transmit signal carrier selector that provides diversified options, a receive signal carrier selector that is strictly synchronized with the transmit signal carrier selector, and a group of fast Fourier transformation modules to output a binary demodulation signal with jamming eliminated. The method includes: binary information division; index modulation and information modulation; information loading and hopping; information transmission, de-hopping, and jamming filtering; and calculation of the jamming probability and an average bit error rate. The present disclosure combines orbital angular momentum modes and subcarrier frequencies to form OAM mode-subcarrier frequency pair sets so as to diversify information transmission carriers, and performs simultaneously modulation and hopping to increase a spectrum efficiency and enhance the anti-jamming capability.

SYSTEM AND METHOD FOR SUPPRESSING UPLINK INTERFERENCE SIGNALS GENERATED IN A MULTI-SPOT SPACE COMMUNICATION SYSTEM
20220094427 · 2022-03-24 ·

A method for suppressing interference signals generated between satellite access stations of a multi-spot communication system is implemented by a distributed on-board and ground subsystem which comprises, on board a multi-spot communication payload, one or more opposition matrices, switches of an input switch assembly connected to the output of the reception sources of the reception antenna, and switches of an output selection ring connected upstream of the transmission sources of the transmission antenna, and, on the ground, a satellite access station GWt having a communication spectrum monitoring system CSM and a computer. The suppression method comprises a set of steps for testing the satellite accesses of the different stations GW, enabling each opposition matrix to be set selectively. The multi-spot space communication system incorporating the subsystem for suppressing the interference signals is described.

Mitigation of partial band jamming for satellite communications

A transmitter, including a signal processor programmed to generate, based on input serial data, for each of an integer number of subcarriers mutually orthogonal to each other, a respective first parallel data stream. The signal processor is further programmed to modulate each of the integer number of subcarriers respectively with the respective parallel stream to generate the integer number of data-modulated subcarriers. The signal processor is further programmed to modulate a single carrier occupying a same bandwidth as the integer number of subcarriers with a unique word and one or more pilot symbols to generate a second signal. The signal processor combines the first signal and second signal to generate a third signal. The signal processor generates an output signal by applying a transmit filter to the third signal.

Automatic external RF gain calibration and continuous jamming measurement

A system and method provide automatic RF path gain calibration independent of RF interference levels to preserve solution trust capabilities. After a system is powered ON, or a new antenna is attached (hot swap), a smart antenna assembly combined with a jammer power estimator within an RF receiver functions to autonomously measure internal gains within the RF path, calibrate the new antenna installation, and thereby measure a level of interference associated with the external environment from that point forward. A controller commands the antenna calibration retrieving antenna details and RF path gain calibration while measuring local jamming at the receiver input. Should the controller determine a level of jamming effectiveness is present, it offers a user a display of the local jamming levels enabling the user accurate theater decision making regarding the accuracy and availability of desirable signal.

Spatial energy rank detector and high-speed alarm

A method, system, and computer program are described for identifying the presence of narrowband signals within a wide instantaneous bandwidth by exploiting the spatial diversity of the received signals using an array aperture to provide detection capability. For example, the method includes receiving and channelizing digitized signals into signals with a narrow bandwidth of interest. The method further includes estimating covariance matrices associated with the signals, determining a set of Eigenvalues for the covariance matrices, and analyzing each Eigenvalue to determine a rank change estimate. The method further includes identifying one or more of the signals that have a positive rank change estimate, computing a beam forming weight and direction estimate for each signal that has a positive rank change estimate, and outputting an indication of the signals that have a positive rank change estimate including one or more of fine timing information, the beamforming weights, and the direction estimate.

SPATIAL ENERGY RANK DETECTOR AND HIGH-SPEED ALARM

A method, system, and computer program are described for identifying the presence of narrowband signals within a wide instantaneous bandwidth by exploiting the spatial diversity of the received signals using an array aperture to provide detection capability. For example, the method includes receiving and channelizing digitized signals into signals with a narrow bandwidth of interest. The method further includes estimating covariance matrices associated with the signals, determining a set of Eigenvalues for the covariance matrices, and analyzing each Eigenvalue to determine a rank change estimate. The method further includes identifying one or more of the signals that have a positive rank change estimate, computing a beam forming weight and direction estimate for each signal that has a positive rank change estimate, and outputting an indication of the signals that have a positive rank change estimate including one or more of fine timing information, the beamforming weights, and the direction estimate.

SYSTEM FOR MEASURING THE TEMPERATURE IN A SEVERE ATMOSPHERE ENVIRONMENT, RECEPTION ANTENNA
20210108969 · 2021-04-15 ·

A system for measuring temperature in a sterilization autoclave, including a temperature transducer positionable inside a sterilization chamber of the autoclave and a receiver positionable outside the sterilization chamber. The receiver includes a reception antenna and a receiving electronic circuit connectable with a process controller of the autoclave. The receiving electronic circuit is configured to receive a temperature signal through the reception antenna, provide a control signal as a function of the temperature signal, and transmit the control signal to the process controller. The temperature transducer includes a hermetically closable transducer housing, temperature probes, a transmission antenna, an electronic transduction circuit, and a primary battery. The reception antenna of the receiving device is configured to transmit signals at two or more different frequencies.

PHASED-ARRAY ANTI-JAMMING DEVICE AND METHOD
20210048535 · 2021-02-18 · ·

A phased array anti-jamming device, comprising a plurality (N) of antennas and a plurality of splitters connected to the antennas and adapted to split an RF stream received from the antennas. The phased array anti-jamming device further includes at least one digital signal processor adapted to digitally analyze a digital output of digital processing channels and to split the output into a plurality of digital down converted representations of respective analog outputs of a plurality of analog digital processing channels in a plurality of different frequencies and calculate at least one instructions selected from phase shift, amplification, and attenuation instructions for each one of the plurality of antennas per each one of the plurality of different frequencies. The phased array anti-jamming device further includes a plurality of phase shifter groups a plurality of group combiners and a main combiner adapted to sum outputs of the plurality of group combiners.