Raytheon Technologies (Canada)

Abstract Observations of atmospheric carbon dioxide (CO 2 ) are expected to play a critical role in monitoring, reporting, and verification designed to track progress toward the reduction goals of greenhouse gas emissions. In this study, we construct a comprehensive regional carbon budget for seven National Climate Assessment regions of the contiguous United States (CONUS) over 2015–2020. We demonstrate that lateral carbon movement across regions, along with their resulting endpoint CO 2 emissions, represent a major contributor to the interpretation of regional net surface‐atmosphere fluxes of CO 2 . When accounting for lateral carbon fluxes, “top‐down” flux estimates from v10 Orbiting Carbon Observatory 2 (OCO‐2) Modeling Intercomparison Project (MIP) agree, within uncertainty, with inventory‐based carbon stock change estimates in six out of seven National Climate Assessment regions ‐ except for the Southwest. The total net carbon exchange from the top down is 925 ± 339 Tg carbon per year (Tg C/year), consistent with the 974 Tg C/year estimate from the inventory. Notably, lateral carbon flows in the form of harvested wood products and riverine carbon burial are responsible for an estimated 16% of the total carbon stock changes occurring across CONUS. Averaged over the seven regions, accounting for lateral transport and their endpoint carbon emissions improves the consistency between inventory and top‐down estimates by 31%. Our study presents a roadmap for reconciling the inventories and top‐down atmospheric inversions at sub‐national scale and highlights the importance of accurate representation of lateral carbon flows for using top‐down estimates with national inventories.

Abstract The applications of advanced ceramics, composites and coatings in mineral, mining, fuel production, and processing are reviewed. The materials include oxide and non‐oxide ceramics (specifically SiC‐based), ceramic–ceramic, and ceramic–metal composites, coatings on metallic components where functional application properties can be achieved. Some principles of materials selection, specifically for erosion wear and corrosion applications, and manufacturing are considered. The examples of the successful development and processing of ceramics, coatings, and composites with manageable structures and phase compositions, in the erosion‐related applications, particularly conducted by the author, are discussed and reviewed. Specifically, industrially employed types of ceramics and processing routes were focused on the considered applications. Particular demands for advanced materials with high reliability and complex shapes or for protective coatings on complex shape steel components and long tubing with inner surface protection require novel and optimized processing. The factors affecting erosion and erosion–corrosion resistance and the paths for the erosion resistance enhancement of ceramic and coating materials are considered. Ceramic components design, technology, and installation features are reviewed.

The objective of this article is to outline the sense-and-adapt capabilities of Canada's Third-Generation High Frequency Surface Wave Radar (3rd Gen HFSWR). This system is an evolution of Raytheon's pioneering SWR503 radar.

Three different approaches to calculation of internal structure of bokeh image in camera lenses with two aspheric surfaces are analyzed and compared – the transfer function approach, the beam propagation approach and direct raytracing in an optical design software. The transfer function approach is the fastest and provides accurate results when peak-to-valley of mid-spatial frequency phase modulation induced at the lens exit pupil is below λ/10. Aspheric surfaces are shown to contribute to the bokeh structure differently increasing the complexity of bokeh image especially for offaxis bokeh.

With the rapidly growing use of commercial Unmanned Aerial Vehicles (UAVs), integrating civilian UAVs into the controlled airspace seems inevitable. We investigate the problem of associating correct labels to different radar tracks, specifically to distinguish UAV tracks among others (such as aircraft and birds). To this end, three plausible civilian applications involving UAVs are proposed and studied. Then, for each application, a number of UAV tracks are simulated and merged into an existing dataset of real aircraft and bird tracks. We show that, with a chosen set of track features, the simulated UAV tracks are correctly labeled with 99% accuracy.

A lightweight single-aperture and multi-spectral sensor operating from Visible to LWIR has been designed, manufactured and tested exploiting a Three Mirror Anastigmat (TMA) telescope featuring thin free-form mirrors electroformed from negative masters. Manufacturing complexity is in place only for the master realization, the contribution of which to the sensor cost decreases with the number of replicas. The TMA, suitable for airborne surveillance applications, has F/no. 1.4, focal length 136 mm and field of view 4.3° × 3.1°, and provides two channels, in the MWIR-LWIR and in the visible waveband. The nominal contrast is better than 75% in the visible at 25 cycles/mm. Electroformed 1 mm thick mirrors keep the sensor mass below 3 kg. Stray light and thermo-structural design has been done to comply with airborne conditions.

This paper describes a Wide Area Integrated Maritime Surveillance (WAIMS) system based on High Frequency Surface Wave Radar (HFSWR) for monitoring surface and low-level air activity within the 200 nm Exclusive Economic Zone (EEZ). The system is designed to help authorities to locate and identify illegal activities. In particular, we investigate the bias problem from a nonlinear latitude and longitude transformation. The geometric relationship between a sensor and a target position is formulated. Then using Taylor series, an analysis of the nonlinear transformation bias is done with comparison of calculated and simulated results.

Protection of national sovereignty requires the ongoing, systematic collection of data from a range of sensors and other sources and the assembly and maintenance of a picture of the position, classification, identification and movement of cooperative and non-cooperative ships, aircraft and hazards in the exclusive economic zone. Integrated maritime surveillance maintains a continuous and affordable real-time picture of ship and aircraft tracks to beyond the 200 nautical mile limit of the EEZ using land based HF and microwave radar systems. The system associates ancillary data from other sources to provide a knowledge-based "recognized maritime picture" and the most effective surveillance of all significant targets within the EEZ. Overlays of GIS referenced data such as sea-state, currents, ice, water temperature, phytoplankton, etc., can be included to support the deployment of air and surface assets and maximize their effectiveness in dealing with fisheries protection, drug interdiction, illegal immigration, terrorist threats, search and rescue and other aspects of national sovereignty.

In this paper we consider the effect of surface target dynamics on the detection performance of coherent radar. The echo from a surface target traveling with a constant velocity, that is not radial to the radar look direction or constant rate acceleration is represented in the form of chirp function. This is a simplistic model that must be extended to account for other periodic accelerations acting on the target. The dominant periodic acceleration is the radial surge component that may result in the smearing of the targets Doppler. This radial surge component is a result of the interaction of the target with the ocean wave. This effect must be taken into account when determining the optimum coherent integration time (CIT). In this paper we extend the model to accommodate an echo from a periodic accelerating target with a frequency-modulated signal that represents the surge component. The optimum CIT is derived based on maximizing the signal-to-noise ratio (SNR) at the matched filter output. The results are verified based on data collected from a high frequency surface wave radar (HFSWR) operating at 15 MHz.

We propose a novel scheme for using high frequency ocean surveillance radar (HFOSR) to detect slow weak target echoes embedded in temporally correlated sea clutter having a continuous spectrum. General Doppler processing CFAR detection of ships in ocean surveillance radar is usually inhibited by the continuous high order sea clutter. Conventional subspace methods can be utilized to enhance the detection, but they deteriorate dramatically in the presence of correlated sea clutter. In our paper an adaptive sea clutter filtering is introduced which improves the threshold and accuracy of the subspace detection method. Both simulated and real ship targets are used to verify the effectiveness of our proposed method.