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This article presents development of a UAV based frequency modulated continuous wave (FMCW) radar system for remotely sensing the water contained within snowpacks. To make the radar system compatible with the payload requirements of small UAV platforms, the radar electronics are implemented with CMOS technology, and the antenna is implemented as an extremely compact and lightweight metasurface (MTS) antenna. This article will discuss how the high absorption losses of snowpacks lead to dynamic range requirements much stricter than FMCW radars used for automotive and other sensing applications, and how these requirements are met through antenna isolation, leakage calibration and exploitation of the range correlation effect. The article discusses in detail the implementation of the radar system, the CMOS microwave and digital circuitry, and the MTS antenna. The developed radar was mounted on a drone and conducted surveys in both Idaho and Alaska during the 2022-2023 winter season. We present several of those field results.

INTRODUCTION: Emergency departments (ED) care for societys most vulnerable older adults who present with exacerbations of chronic disease at the end of life, yet the clinical paradigm focuses on treatment of acute pathologies. Palliative care interventions in the ED capture high-risk patients at a time of crisis and can dramatically improve patient-centred outcomes. This study aims to implement and evaluate Primary Palliative Care for Emergency Medicine (PRIM-ER) on ED disposition, healthcare utilisation and survival in older adults with serious illness. METHODS AND ANALYSIS: This is the protocol for a pragmatic, cluster-randomised stepped wedge trial to test the effectiveness of PRIM-ER in 35 EDs across the USA. The intervention includes four core components: (1) evidence-based, multidisciplinary primary palliative care education; (2) simulation-based workshops; (3) clinical decision support; and (4) audit and feedback. The study is divided into two phases: a pilot phase, to ensure feasibility in two sites, and an implementation and evaluation phase, where we implement the intervention and test the effectiveness in 33 EDs over 2 years. Using Centers for Medicare and Medicaid Services (CMS) data, we will assess the primary outcomes in approximately 300 000 patients: ED disposition to an acute care setting, healthcare utilisation in the 6 months following the ED visit and survival following the index ED visit. Analysis will also determine the site, provider and patient-level characteristics that are associated with variation in impact of PRIM-ER. ETHICS AND DISSEMINATION: Institutional Review Board approval was obtained at New York University School of Medicine to evaluate the CMS data. Oversight will also be provided by the National Institutes of Health, an Independent Monitoring Committee and a Clinical Informatics Advisory Board. Trial results will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT03424109; Pre-results.

This article presents development of CMOS system-on-chip spectrometer processor for Spaceborne Earth Science, Planetary Science and Astronomy. The developed chip is intended for use in rotational emission spectroscopy observations from microwave to sub-millimeter wavelengths performed from Earth orbiting or deep space exploration spacecraft. The article first provides an overview of rotational spectroscopy for space sciences and highlights some of the important results achieved in Earth science, planetary science, and astronomy. The article then discusses the need for smaller and more compact spectrometer instruments across these three space science areas, which motivates this work. Then key considerations in development of spectrometer processors for space science are discussed including the significance including bandwidth, quantization efficiency and spectral channel shapes. The article then highlights detailed design of the developed spectrometer processor focusing on the many calibration techniques included to allow the chip to adapt to operations in space environments where large temperature ranges and high radiation levels are encountered. Presented measurements demonstrate the spectrometer processor operates up to 12.8 GS/s to provide up to 6.4 GHz of processing bandwidth with a frequency resolution of 8192 spectral channels and an analog resolution of 4 bits while consuming only 3960 mW of total DC power.

This paper presents a Ku -band (14-16 GHz) CMOS frequency-modulated continuous-wave (FMCW) radar transceiver developed to measure dry-snow depth for water management purposes and to aid in retrieval of snow water equivalent. An on-chip direct digital frequency synthesizer and digital-to-analog converter digitally generates a chirping waveform which then drives a ring oscillator-based Ku -Band phase-locked loop to provide the final Ku -band FMCW signal. Employing a ring oscillator as opposed to a tuned inductor-based oscillator (LC-VCO) allows the radar to achieve wide chirp bandwidth resulting in a higher axial resolution (7.5 cm), which is needed to accurately quantify the snowpack profile. The demonstrated radar chip is fabricated in a 65-nm CMOS process. The chip consumes 252.4 mW of power under 1.1-V supply, making its payload requirements suitable for observations from a small unmanned aerial vehicle.

This paper presents an overview of a sub-orbital flight demonstration with a 183 GHz and 540–600 GHz limb-sounding instrument aboard a stratospheric ballooncraft. The 183 GHz band provides soundings of stratospheric H2O and is implemented with a hybrid CMOS-InP receiver architecture which provides excellent sensitivity while remaining compact (162 g) and offering an extremely low DC power consumption (0.62 W). The 540–600 GHz channel sounds stratospheric O3 and uses a combination of a CMOS local oscillator, GaAs Schottky mixer and micro-electro-mechanical-system (MEMS) RF switch for calibration, again offering competitive form factor (1.4 Kg) and low DC power consumption (6.6 W) compared to prior instruments. The instrument was flown on the NASA Reck-Tang Limb-sounding Experiment (ReckTangLE) ballooncraft and performed atmospheric soundings across New Mexico and Northwestern Texas on Oct. 17 2019.

In this article, we characterized the charge trapping and detrapping behaviors of charge-trap transistors (CTTs) in standard 28-nm CMOS technology and formulated its programmable threshold voltage ( $V_{\mathrm {TH}}$ ). Both thin-oxide and thick-oxide CTT devices are measured, modeled, and analyzed. More than 50- and 100-mV continuous $V_{\mathrm {TH}}$ tuning ranges are achieved for thin and thick oxide devices, respectively. Multiple cycles of programming and erasing operations are demonstrated; however, the reliability needs to be solved in the future. To utilize the developed programmable threshold model, a nonvolatile memory (NVM) cell and an analog arithmetic unit (AAU) are proposed and simulated as two proof-of-concept CTT-based designs.

Digital circuits implemented in CMOS technology have been the workhorses of high performance computer processors for more than a decade, following Moore's law with exponentially increasing integration and performance. Driven by lower cost, increasing performance, and mixed-signal benefits, CMOS technology also has found increasing use in analog, and more recently, RF applications. Now, with transistor performance still improving, wires are becoming the limiting factor for speed and performance by imposing limits on communication bandwidth and latency between processing cores and memories, both off-and on-chip. Communication and circuit techniques, developed mainly for narrow band-wireless RF communication can help increase the wired communication speed in digital systems. This approach, dubbed RF Interconnect (RF-I), picks up speed for on-board and on-chip applications, changing the communication paradigm from the old parallel unidirectional time-shared bus to new transmission lines enabling reconfigurable communication using both frequency and code division multiple access techniques.