We introduce a 512 × 424 time-of-flight (TOF) depth image sensor designed in a TSMC 0.13 μm LP 1P5M CMOS process, suitable for use in Microsoft Kinect for XBOX ONE. The 10 μm × 10 μm pixel incorporates a TOF detector that operates using the quantum efficiency modulation (QEM) technique at high modulation frequencies of up to 130 MHz, achieves a modulation contrast of 67% at 50 MHz and a responsivity of 0.14 A/W at 860 nm. The TOF sensor includes a 2 GS/s 10 bit signal path, which is used for the high ADC bandwidth requirements of the system that requires many ADC conversions per frame. The chip also comprises a clock generation circuit featuring a programmable phase and frequency clock generator with 312.5-ps phase step resolution derived from a 1.6 GHz oscillator. An integrated shutter engine and a programmable digital micro-sequencer allows an extremely flexible multi-gain/multi-shutter and multi-frequency/multi-phase operation. All chip data is transferred using two 4-lane MIPI D-PHY interfaces with a total of 8 Gb/s input/output bandwidth. The reported experimental results demonstrate a wide depth range of operation (0.8-4.2 m), small accuracy error ( 1%), very low depth uncertainty ( 0.5% of actual distance), and very high dynamic range ( 64 dB).

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The System for Automated Geoscientific Analyses (SAGA) is an open-source Geographic Information System (GIS), mainly licensed under the GNU General Public License. Since its first release in 2004, SAGA has rapidly developed from a specialized tool for digital terrain analysis to a comprehensive and globally established GIS platform for scientific analysis and modeling. SAGA is coded in C++ in an object oriented design and runs under several operating systems including Windows and Linux. Key functional features of the modular organized software architecture comprise an application programming interface for the development and implementation of new geoscientific methods, an easily approachable graphical user interface with many visualization options, a command line interpreter, and interfaces to scripting and low level programming languages like R and Python. The current version 2.1.4 offers more than 700 tools, which are implemented in dynamically loadable libraries or shared objects and represent the broad scopes of SAGA in numerous fields of geoscientific endeavor and beyond. In this paper, we inform about the system's architecture, functionality, and its current state of development and implementation. Further, we highlight the wide spectrum of scientific applications of SAGA in a review of published studies with special emphasis on the core application areas digital terrain analysis, geomorphology, soil science, climatology and meteorology, as well as remote sensing.

High levels of nitrate leaching losses from potato rotation systems have caused concerns for both drinking water quality and aquatic ecosystem protection in Prince Edward Island (PEI). Paired-field experiments were carried out in commercial fields to evaluate the potential of delayed plowing forages within potato rotation from fall to spring on reducing nitrate leaching at two separate sites in PEI during 2010 and 2013. Monitoring showed that fall plowing resulted in elevated tile-drain nitrate concentrations compared to spring plowing, probably mainly due to crop residue mineralization during fall which was hastened by earlier herbicidal termination of forage (i.e., herbicidal killing) at Site 1. A similar trend was also observed regarding nitrate concentrations of shallow groundwater at Site 2 during the forage phase. The practice of delaying the plowing of forages and/or associated earlier herbicidal termination of forage until spring reduces forage-phase nitrate leaching loss by 20 to 61%, and should therefore be encouraged for nitrate mitigation. The study also demonstrated that only a small fraction (9.6 to 22%) of the fall plow-down forages decayed during the forage phase and a large portion was retained in the soil into the next season. Growers should consider accounting for some of the carried-over N for the subsequent crops regardless implementing fall or spring plowing.

Interest in 3D depth cameras has been piqued by the release of the Kinect motion sensor for the Xbox 360 gaming console [1,2,3]. This paper presents the pixel and 2GS/s signal paths in a state-of-the-art Time-of-Flight (ToF) sensor suitable for use in the latest Kinect sensor for Xbox One. ToF cameras determine the distance to objects by measuring the round trip travel time of an amplitudemodulated light from the source to the target and back to the camera at each pixel. ToF technology provides an accurate high pixel resolution, low motion blur, wide field of view (FoV), high dynamic range depth image as well as an ambient light invariant brightness image (active IR) that meets the highest quality requirements for 3D motion detection.Depth and active IR images are produced by combining multiple images that are captured at different phase relationships of the clocks provided to the light source and pixel array. The captures are taken in rapid temporal succession to avoid motion blur. In addition, high differential dynamic range is necessary to simultaneously render high-reflectivity objects near the camera and lowreflectivity objects far from the camera. High dynamic range is realized by allowing each pixel to independently select the best shutter time (multi-shutter) and the best amplifier gain setting (multi-gain) at each capture.Due to the multiple captures that need to be taken in rapid succession and the high dynamic range requirements, ADC conversion must be performed many times per capture and due to noise considerations cannot happen simultaneously with integration. Therefore a high-bandwidth 2GS/s 10b, column-parallel ADC is employed. Noise and mismatches are cancelled by using a completely differential design from pixel through ADC.The ToF chip includes a 512×424 pixel array with 10μm pixel pitch fabricated in a standard TSMC 0.13μm CMOS LP 1P5M process. The 60% fill-factor (effective with μLens) pixel achieves a modulation contrast (MC) of 67% (measured at 50MHz) and a responsivity of 0.14A/W at 860nm. The chip can operate at high modulation frequencies of up to 130MHz to extract maximum depth quality while minimizing system light-source power. The schematic of the fully differential pixel design with a simplified detector plan is shown in Fig. 7.6.