An improved circuit configuration is disclosed for calibrating and/or verifying the operation of phase shifters in a phased array radar system. In one illustrative embodiment, a method includes: (i) programming a set of phase shifters to convert a radio frequency signal into a set of channel signals; (ii) splitting off a monitor signal from each channel signal while coupling the set of channel signals to a set of antenna feeds; and (iii) while taking the monitor signals in pairs associated with adjacent channels, measuring a relative phase between each pair of monitor signals.

An improved circuit configuration is disclosed for calibrating and/or verifying the operation of phase shifters in a phased array radar system. In one illustrative embodiment, a method includes: (i) programming a set of phase shifters to convert a radio frequency signal into a set of channel signals; (ii) splitting off a monitor signal from each channel signal while coupling the set of channel signals to a set of antenna feeds; and (iii) while taking the monitor signals in pairs associated with adjacent channels, measuring a relative phase between each pair of monitor signals.

Disclosed herein is a system for facilitating performing of motion analysis in a field of interest, in accordance with some embodiments. Accordingly, the system may include a passive sensor, an active sensor, a processing device, a gateway, and a remote monitoring center. Further, the passive sensor and the active sensor is disposed in the field of interest. Further, the passive sensor generates passive sensor data. Further, the active sensor produces second waves, receives transformed waves, and generates active sensor data. Further, the gateway is configured for transmitting the passive sensor data and the active sensor data to the remote monitoring center. Further, the remote monitoring center is configured for performing the motion analysis. Further, the remote monitoring center may include a remote processing device configured for combining the passive sensor data and the active sensor data and generating motion information based on the combining.

A radar system transmits pulses towards a target and receives pulses reflected back therefrom. Based on samples (of the received pulses) corresponding to a CPI, a first 2D matrix having a slow-time index and a fast-time index is generated. A slow-time FFT is performed to convert the slow-time index to a Doppler bin index to produce a second 2D matrix having the Doppler bin index and the fast-time index. Thereafter, a 1D interpolation is performed along the Doppler bin index to produce a third 2D matrix having a Velocity bin index and the fast-time index. Thereafter, a fast-time FFT is performed to convert the fast-time index to a Range bin index to produce a fourth 2D matrix having the Velocity bin index and a Range bin index. A distance to and a velocity of a target is determined based on the fourth 2D matrix.

A radar system transmits pulses towards a target and receives pulses reflected back therefrom. Based on samples (of the received pulses) corresponding to a CPI, a first 2D matrix having a slow-time index and a fast-time index is generated. A slow-time FFT is performed to convert the slow-time index to a Doppler bin index to produce a second 2D matrix having the Doppler bin index and the fast-time index. Thereafter, a 1D interpolation is performed along the Doppler bin index to produce a third 2D matrix having a Velocity bin index and the fast-time index. Thereafter, a fast-time FFT is performed to convert the fast-time index to a Range bin index to produce a fourth 2D matrix having the Velocity bin index and a Range bin index. A distance to and a velocity of a target is determined based on the fourth 2D matrix.

The disclosed systems, structures, and methods are directed to an object detection system, employing a receiver configured to receive a signal reflected from an object, an analog-to-digital converter (ADC) configured to convert the received signal into a digital signal, a pre-processor configured to improve a signal-to-noise (SNR) of the digital signal and to generate a pre-processed signal corresponding to the digital signal, a parameter extractor configured to calculate a number of reference cells M and a multiplication factor K.sub.0, and a Constant False Alarm Rate (CFAR) processor configured to analyze a cell-under-test (CUT) and M reference cells in accordance with the number of reference cells M and the multiplication factor K.sub.0 to detect the presence of the object.

Detection of a radar target from a received radar signal includes computing a vector of filter weights dependent upon a steering vector and determining a threshold value dependent upon a designated probability of false alarm. The vector of filter weights is applied to samples of the received radar signal at a test cell, corresponding to a test range, to provide a filtered test signal and a test power of the filtered test signal is computed. The weights are also applied to samples of the received radar signal at a number of reference cells, to produce filtered reference signals. A reference power is computed from the filtered reference signals and the radar target is detected at the test range when a ratio of the test power to the reference power exceeds the threshold value.

Radio frequency motion sensors may be configured for operation in a common vicinity so as to reduce interference. In some versions, interference may be reduced by timing and/or frequency synchronization. In some versions, a master radio frequency motion sensor may transmit a first radio frequency (RF) signal. A slave radio frequency motion sensor may determine a second radio frequency signal which minimizes interference with the first RF frequency. In some versions, interference may be reduced with additional transmission adjustments such as pulse width reduction or frequency and/or timing dithering differences. In some versions, apparatus may be configured with multiple sensors in a configuration to emit the radio frequency signals in different directions to mitigate interference between emitted pulses from the radio frequency motion sensors.

Radio frequency motion sensors may be configured for operation in a common vicinity so as to reduce interference. In some versions, interference may be reduced by timing and/or frequency synchronization. In some versions, a master radio frequency motion sensor may transmit a first radio frequency (RF) signal. A slave radio frequency motion sensor may determine a second radio frequency signal which minimizes interference with the first RF frequency. In some versions, interference may be reduced with additional transmission adjustments such as pulse width reduction or frequency and/or timing dithering differences. In some versions, apparatus may be configured with multiple sensors in a configuration to emit the radio frequency signals in different directions to mitigate interference between emitted pulses from the radio frequency motion sensors.

Techniques are disclosed for systems and methods to provide remote sensing imagery for mobile structures. A remote sensing imagery system includes a remote sensing assembly with a housing mounted to a mobile structure and a coupled logic device. The logic device is configured to receive radar returns corresponding to a detected target from the radar assembly, determine a target radial speed corresponding to the detected target, determine an adaptive target speed threshold, and then generate remote sensor image data based on the remote sensor returns, the target radial speed, and the adaptive target speed threshold. Subsequent user input and/or the sensor data may be used to adjust a steering actuator, a propulsion system thrust, and/or other operational systems of the mobile structure.