Abstract: A method for building a coherent radar cross-section (RCS) model database for real-time dynamic simulation of range-Doppler radars is disclosed. The database may be used with radar sensors that employ different waveforms. A pre-processing operation before the dynamic simulation performs fast Fourier Transforms (FFTs) to interpolate the target frequency responses from the database to match the frequency samplings of the radar used in the dynamic simulation. The method determines the frequency responses of the targets to a reference chirp in a coherent processing interval (CPI) and the radial velocities of the targets relative to the radar at the time of the reference chirp. The method extrapolates, using FFTs, the frequency responses of the targets to the reference chirp across the velocity dimension based on the relative radial velocities to determine the frequency responses of the targets to the other chirps across the CPI, reducing the computational burden for the simulation.

Abstract: A method for building a coherent radar cross-section (RCS) model database for real-time dynamic simulation of range-Doppler radars is disclosed. The database may be used with radar sensors that employ different waveforms. A pre-processing operation before the dynamic simulation performs fast Fourier Transforms (FFTs) to interpolate the target frequency responses from the database to match the frequency samplings of the radar used in the dynamic simulation. The method determines the frequency responses of the targets to a reference chirp in a coherent processing interval (CPI) and the radial velocities of the targets relative to the radar at the time of the reference chirp. The method extrapolates, using FFTs, the frequency responses of the targets to the reference chirp across the velocity dimension based on the relative radial velocities to determine the frequency responses of the targets to the other chirps across the CPI, reducing the computational burden for the simulation.

Abstract: A method for building a coherent radar cross-section (RCS) model database for real-time dynamic simulation of range-Doppler radars is disclosed. The database may be used with radar sensors that employ different waveforms. A pre-processing operation before the dynamic simulation performs fast Fourier Transforms (FFTs) to interpolate the target frequency responses from the database to match the frequency samplings of the radar used in the dynamic simulation. The method determines the frequency responses of the targets to a reference chirp in a coherent processing interval (CPI) and the radial velocities of the targets relative to the radar at the time of the reference chirp. The method extrapolates, using FFTs, the frequency responses of the targets to the reference chirp across the velocity dimension based on the relative radial velocities to determine the frequency responses of the targets to the other chirps across the CPI, reducing the computational burden for the simulation.

Abstract: One or more embodiments of a device or structure for medical testing. The structure may include a shell defining an interior of the structure, at least one workstation in the interior of the structure, at least one window in the shell, each of the at least one workstation including one of the at least one window communicating between the respective workstation and an exterior of the structure, and an air control system configured to filter air and control air pressure in the interior of the structure.

Abstract: A method is disclosed for augmenting the SBR model used in EM field simulation by modeling the specular coherent and diffuse incoherent components of the field scattered by rough surfaces using statistical characteristics of surface roughness. For each projected ray-tube footprint, the magnitude of the coherent radiated field is attenuated with a scalar factor, while the incoherent radiated field is modulated by a random magnitude and phase. Both corrections are based on the statistical characteristics of surface roughness. Multiplying the incoherent field with a randomly generated phase renders it in a mathematically coherent form, which allows the method to generate a statistically viable instance of the total (i.e. coherent plus incoherent) field scattered by a rough surface. The results reproduce the field and power statistics (i.e. mean and variance) observed from direct SBR simulations using an ensemble of explicitly rendered rough surface geometry models, with a significant reduction in computation.

Abstract: Systems and methods are provided for a computer-implemented method for generating a display of radar returns. A geometry data structure is accessed that identifies characteristics of a region of interest including dimensions and movement of one or more objects in the region of interest. A pulse of a plurality of rays is transmitted from an antenna position into the region of interest and the velocities of returns of the rays are captured at a receiver position after the rays have interacted with the one or more objects. Each ray return is assigned into one of a plurality of bins based on the velocity of that ray. A Fourier transform is performed using the binned data to obtain a system response at discrete time intervals. The system response at the discrete time intervals is transformed into Doppler velocity data, and the Doppler velocity data is stored and displayed on a graphical user interface.

Abstract: A method for building a coherent radar cross-section (RCS) model database for real-time dynamic simulation of range-Doppler radars is disclosed. The database may be used with radar sensors that employ different waveforms. A pre-processing operation before the dynamic simulation performs fast Fourier Transforms (FFTs) to interpolate the target frequency responses from the database to match the frequency samplings of the radar used in the dynamic simulation. The method determines the frequency responses of the targets to a reference chirp in a coherent processing interval (CPI) and the radial velocities of the targets relative to the radar at the time of the reference chirp. The method extrapolates, using FFTs, the frequency responses of the targets to the reference chirp across the velocity dimension based on the relative radial velocities to determine the frequency responses of the targets to the other chirps across the CPI, reducing the computational burden for the simulation.

Abstract: A method and apparatus for replacing a tendon flex bearing on a tension leg platform includes installing a tendon tensioning tool on the Length Adjustment Joint (LAJ) of a tendon and providing a supplemental buoyancy module on the tendon. The tendon tensioning tool is used to disengage the slips from the top tendon connector. The buoyancy of the supplemental buoyancy module may then be adjusted to support the tendon whereupon the tendon tensioning tool may be disengaged permitting removal and replacement of the tendon flex bearing. Following installation of the new (or refurbished) flex bearing, the steps of the procedure may be reversed to return the tendon to its normal operating state. In certain embodiments, top clamp actuation means is provided in the tendon tensioning tool for removing slips from the top clamp.

Abstract: A method and apparatus for replacing a tendon flex bearing on a tension leg platform includes installing a tendon tensioning tool on the Length Adjustment Joint (LAJ) of a tendon and providing a supplemental buoyancy module on the tendon. The tendon tensioning tool is used to disengage the slips from the top tendon connector. The buoyancy of the supplemental buoyancy module may then be adjusted to support the tendon whereupon the tendon tensioning tool may be disengaged permitting removal and replacement of the tendon flex bearing. Following installation of the new (or refurbished) flex bearing, the steps of the procedure may be reversed to return the tendon to its normal operating state. In certain embodiments, top clamp actuation means is provided in the tendon tensioning tool for removing slips from the top clamp.

Abstract: A deck mounted pull riser tensioning system for a floating platform or vessel includes at least two cylinders having a cylinder body supported at an upper or lower end on a deck or tensioner support structure of the platform or vessel in spaced apart relation with the cylinder rods extending downwardly from the cylinder body, or vice versa. A load structure member is connected to lower ends of the cylinder rods or bodies and has an opening therethrough for receiving a portion of a riser extending from the seafloor. A vertically adjustable riser attachment supported on the load structure member over the opening attaches to a portion of the riser extending through the opening and generally centrally between the cylinders. The cylinders pull upwardly on the load structure member to exert an upward tensioning force on the riser at the location of the riser attachment.

Abstract: A tendon for mooring a tension leg platform having an uppermost pipe segment with a reduced diameter compared to at least one of the lower pipe segments. The tendon is watertight and sealed from the ocean environment, preferably filled with air at one atmosphere of pressure. One or more interior bulkheads may be included to divide the tendon into multiple compartments. The reduced outer diameter of the uppermost pipe segment provides reduced drag due to waves and currents and accommodates smaller tendon support buoys and vortex fairings, while the greater diameter of the lower pipe segment provides for increased tendon buoyancy.