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Using a Software-Defined Radio Ground Station for a Small Satellite Mission
No full textIn January 2025, InnoCube, a 3U CubeSat was launched with the Transporter-12 mission, becoming the 31st academic satellite of TU Berlin. The technology demonstration mission is the first one at TU Berlin which uses software-defined radio to operate the satellite in the amateur UHF band. The ground station is based on software-defined radio, which has been a vital part of the development of the communication system of InnoCube. Integration into the ground segment is a logical step in the test-as-you-fly philosophy of the mission. The ground segment consists of a SDR which is paired to a power amplifier which includes the switching logic, a cavity filter and a low-noise amplifier using a high gain quad antenna. The ground station is controlled with GNURadio. The ground station paths are verified separately, for receiving, different small satellites operating over Berlin are decoded. Uplink is verified with a spectrum analyzer, vector network analyzer and ground tests. After launch, the first contact is established within 2 minutes of the satellite being in range. Initial operational challenges included TLE inaccuracy, requiring frequent updates and corrections, as well as evaluating the best station configuration to maximize link performance. This challenge is significantly reduced by using SDRs and real-time adaption of receiving and transmitting frequency, based on live transmissions. By optimizing digital signal processing, downlink capacity could be increased by over 100%. Another challenge of the mission is polarization, as satellite and ground station are both using right-handed circular polarized antennas. Polarization effects of the satellite tumbling and its implications on the link are discussed. As the signal-to-noise ratio is observed for each message, extensive data for each pass is available. Additionally, a carrier-sense is presented to increase the uplink capacity for a semi-duplex communication channel. Further analysis is discussed between calculated link budget prior to the mission and measured data, highlighting deviations and implementation losses
Novel Orbits for Resilient Launch – Enabling the Optimization of Rideshare Options to Cislunar and GEO Destinations
No full textLaunch and delivery access to cislunar space is a unique challenge that has received increased interest in recent years for a variety of mission applications. Beginning with the CAPSTONE mission and followed by Artemis I CubeSat rideshares, iSpace, Intuitive Machines, KARI, and CLPS landers, launches to cislunar space have increased dramatically. With launches increasing and other expected missions deploying to this valuable domain, evaluations of efficient and sustainable launch approaches are highly relevant to future operations. Launching to cislunar space utilizing the benefit of third-body perturbations from the Sun and Moon has been demonstrated by multiple missions including the ARTEMIS mission, GRAIL, CAPSTONE, iSpace, and KARI, to name a few. These multi-body orbits are referred to herein as “novel orbits” due to their lack of traditional Keplerian behavior.
There are many benefits to multi-body approaches when accessing cislunar space. One enticing opportunity is to use a single rideshare launch to deploy one mission to cislunar space and a second mission to geosynchronous orbit (GEO), seemingly very different orbital regimes. This increased utility provides mission planners and launch providers with several unique benefits that enhance the overall resilience of launch to both regions of space. This approach is more efficient because it uses new higher-performing launch vehicle options to inject payloads with less fuel to access lunar orbits, offering a 25% reduction compared to direct TLI; a 70+% reduction for Earth-Moon three-body orbits such as Near Rectilinear Halo Orbit (NRHO) compared to direct transfers; and a 30% reduction to GEO itself. This approach also provides a benefit in that missions can relocate to accommodate congested launch sites by providing access to cislunar and GEO from any site such as high latitude or high inclination launch sites.
Using the novel-orbit approach to perform rideshare delivery of multiple payloads to cislunar and GEO orbits offers optimized ride-share for a variety of mission needs. The approach yields daily launch opportunities to accommodate various potential schedule delays due to systems and environmental uncertainties (i.e., weather). This benefit is important when comparing with other launch schemes to cislunar, notably direct launches, which have far more constrained launch period/window options. A final benefit of this approach compared to phasing orbits or electric propulsion orbit raising is that using novel orbits for resilient launch reduces the radiation exposure of space vehicles from trapped radiation in the Earth’s magnetic field, which can be a significant contributor to the total dose spacecraft must be designed to tolerate.
Advanced Space has been maturing this capability for over a decade and has demonstrated its utility for cislunar injection on the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE™) mission. This paper and presentation will provide the technical details on the approach, lessons learned, and key performance parameters for future mission architects to consider when implementing cislunar and GEO missions that can leverage this multi-mission flexible approach for both primary payload and Rideshare missions
Large-Scale Flood Detection and Mapping in the Yangtze River Basin (2016–2021) Using Convolutional Neural Networks With Sentinel-1 SAR Images
No full textSynthetic Aperture Radar (SAR) technology offers unparalleled advantages by delivering high-quality images under all-weather conditions, enabling effective flood monitoring. This capability provides massive remote sensing data for flood mapping, while recent rapid advances in deep learning (DL) offer methodologies for large-scale flood mapping. However, the full potential of deep learning in large-scale flood monitoring utilizing remote sensing data remains largely untapped, necessitating further exploration of both data and methodologies. This paper presents an innovative approach that harnesses convolutional neural networks (CNNs) with Sentinel-1 SAR images for large-scale inundation detection and dynamic flood monitoring in the Yangtze River Basin (YRB). An efficient CNN model entitled FloodsNet was constructed based on multi-scale feature extraction and reuse. The study compiled 16 flood events comprising 32 Sentinel-1 images for CNN training, validation, inundation detection, and flood mapping. A semi-automatic inundation detection approach was developed to generate representative flood samples with labels, resulting in a total of 5296 labeled flood samples. The proposed model FloodsNet achieves 1–2% higher F1-score than the other five DL models on this dataset. Experimental inundation detection in the YRB from 2016 to 2021 and dynamic flood monitoring in the Dongting and Poyang Lakes corroborated the scheme\u27s outstanding performance through various validation procedures. This study marks the first application of deep learning with SAR images for large-scale flood monitoring in the YRB, providing a valuable reference for future research in flood disaster studies. This study explores the potential of SAR imagery and deep learning in large-scale flood monitoring across the Yangtze River Basin, providing a valuable reference for future research in flood disaster studies
Sagebrush, Wildfire, and Homeowners Associations: Climate Adaptation Opportunities in Summit County, Utah
No full textEnvironmental changes and rapidly expanding suburban developments are amplifying wildfire risk in Utah, including in mixed-sagebrush habitats like those in Morgan, Summit, and Wasatch counties along the Wasatch Back. Wildfire risk to people and structures is especially high in the wildland-urban interface (WUI), where homes and buildings intermingle with undeveloped wildlands and natural vegetation that can fuel wildfire. Much of this urban expansion is occurring in the form of large, dispersed developments managed by homeowners associations (HOAs), which often dictate standards for the homes and properties within their purview. Thus, HOAs can play a critical role in supporting wildfire mitigation efforts in the WUI
Faculty Senate Agenda March 31, 2025
No full text3:00 Call to Order Approval of Minutes March 3, 2025 3:05 University Business 3:20 Faculty Senate Business 3:35 Information EPC Report - March 6, 2025 3:40 Report Budget and Faculty Welfare Committee Sustainability Council Policy 323, 378, 389 4:00 Old Business 4:05 New Business 2025-2026 Calendar and Committee Reports President-Elect Nominations Adjourn: 4:30 p
Curriculum Subcommittee Minutes April 3, 2025
No full textApproval of Minutes - March 6, 2025 Program Proposals Semester Course Approval Reviews Other Business Senate Bill 334 update Year-End Summary Other Potential Business Adjourn: 2:36p
General Education Subcommittee Minutes April 3, 2025
No full textCall to Order Approval of Minutes - March 6, 2025 Course Approvals/Removals/Syllabi Approvals New Business Depth designation discussion Election of a committee chair Additional items Adjourn: 9:3
Does \u3ci\u3eBacillus mycoides\u3c/i\u3e Inhibit the Growth of \u3ci\u3eBotrytis cinerea\u3c/i\u3e?
Get PDFBotrytis cinerea is a fungal pathogen shown to threaten agricultural stability. In attempts to find biological controls against such pathogens, some bacteria have demonstrated antifungal properties. Among these, Bacillus mycoides has been identified as a potential producer of antifungal agents that may be relevant to agricultural, horticultural, and medical settings (Kahn et al., 2018). In an effort to identify the effectiveness of B. mycoides as an antifungal biological control, we have tested whether Bacillus mycoides inhibits the fungal growth of Botrytis cinerea
Accuracy of an Automated Approach to Auditory Brainstem Response Analysis
Get PDFHearing loss affects 1.5 billion people worldwide [1] Hearing loss is primarily diagnosed through pure-tone audiometry Pure-tone audiometry is not sensitive to many disorders, especially neural disorders that cause hearing difficulty Pure-tone audiometry cannot identify site-of-lesio
Mathematical Modeling of Color Perception Using Differential Equation
Get PDFColor perception begins in the retina, where three cone types (L, M, S) detect light and initiate neural signals. These signals are processed by horizontal and bipolar cells to form opponent color channels: red-green (RG), yellow-blue (YB), and light-dark (LD). Perception is not solely based on physical input but also shaped by neural adaptation and context.
This project models color perception using a differential equation approach, simulating how color contrast and adaptation emerge from interactions between photoreceptors and lateral inhibition.
We hypothesize that a system of differential equations can model how retinal cone cells respond to and process light intensity, and that this model can anticipate perceptual phenomena such as afterimages and color vision deficiency