skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Long-time non-contact water level measurement with a 5.8-GHz DC-coupled interferometry radar
Flooding caused by tropical cyclones, tsunami, and many other phenomena is one type of natural disaster that occurs all around the world. While these disasters cannot be prevented, the communities can be made more resilient and damages caused by them to lives and infrastructure can be minimized by developing early warning systems. Microwave-based systems provide a non-contact measurement setup to monitor water level, thus requiring low maintenance and operation costs. In this paper, a DC-coupled 5.8-GHz interferometry radar was designed and tested by observing water level in a barrel, which had water poured in and drained out over a long-time period. By adding more gains to the RF chain and removing the gain in the baseband, the proposed water-level monitoring radar system eliminates the requirement of complex DC tuning structure in the previous works. The experiment demonstrated that the proposed water-level monitoring radar system was able to accurately measure the relative position of water with mm-accuracy.  more » « less
Award ID(s):
1760497
PAR ID:
10080349
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
2018 IEEE International Instrumentation and Measurement Technology Conference
Page Range / eLocation ID:
1 to 5
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Accurate continuous measurement of respiratory displacement using continuous wave Doppler radar requires rigorous management of dc offset which changes when a subject changes distance from the radar measurement system. Effective measurement, therefore, requires robust dynamic calibration which can recognize and compensate for changes in the nominal position of a subject. In this paper, a respiratory displacement measurement algorithm is proposed which can differentiate between sedentary and non-sedentary conditions and continuously adapt to provide long-term monitoring of a subject’s sedentary respiration. Arctangent demodulation is an effective means of quantifying continuous displacement using a quadrature Doppler radar, yet it depends on accurate identification of dc offset and dc information contributions in the radar I-Q arc with the subject in a particular position. The dynamic calibration method proposed here is demonstrated to differentiate between sedentary and non-sedentary conditions for six subjects to produce accurate sedentary respiration measurements even when the subject arbitrarily changes position, once the appropriate thresholds are established for the measurement environment. 
    more » « less
  2. At high penetration level of photovoltaic (PV) generators, their abrupt disturbances (caused by moving clouds) cause voltage and frequency perturbations and increase system losses. Meanwhile, the daily irradiation profile increases the slope in the net-load profile, for example, California duck curve, which imposes the challenge of quickly bringing on-line conventional generators in the early evening hours. Accordingly, this paper presents an approach to achieve two objectives: (1) address abrupt disturbances caused by PV generators, and (2) shape the net load profile. The approach is based on employing battery energy storage (BES) systems coupled with PV generators and equipped with proper controls. The proposed BES addresses these two issues by realizing flexible power ramp-up and ramp-down rates by the combined PV and BES. This paper presents the principles, modeling and control design aspects of the proposed system. A hybrid dc/ac study system is simulated and the effectiveness of the proposed BES in reducing the impacts of disturbances on both the dc and ac subsystems is verified. It is then shown that the proposed PV-BES modifies the daily load profile to mitigate the required challenge for quickly bringing on-line synchronous generators. 
    more » « less
  3. null (Ed.)
    Massive data center (DC) energy demands lead to water consumption concerns. This study quantifies on-site and off-site DC water consumption and its holistic impact on regional water availability. This study proposes a new DC sustainability metrics, Water Scarcity Usage Effectiveness (WSUE), that captures the holistic impacts of water consumption on regional water availability by considering electricity and water source locations and their associated water scarcity. We examine the water consumption of various DC cooling systems by tracking on-site water consumption along with the direct and indirect water transfers associated with electricity transmission at the contiguous U.S. balancing authority (BA) level. This study then applies the WSUE metric for different DC cooling systems and locations to compare the holistic water stress impact by large on-site water consuming systems (e.g., via cooling towers) versus systems with higher electrical consumption and lower on-site water consumption such as the conventional use of computer room air conditioner (CRAC) units. Results suggest that WSUE is strongly dependent on location, and a water-intensive cooling solution could result in a lower WSUE than a solution requiring no or less on-site water consumption. The use of the WSUE metric aids in DC siting decisions and DC cooling system design from a sustainability point of view. 
    more » « less
  4. Activity recognition has applications in a variety of human-in-the-loop settings such as smart home health monitoring, green building energy and occupancy management, intelligent transportation, and participatory sensing. While fine-grained activity recognition systems and approaches help enable a multitude of novel applications, discovering them with non-intrusive ambient sensor systems pose challenging design, as well as data processing, mining, and activity recognition issues. In this paper, we develop a low-cost heterogeneous Radar based Activity Monitoring (RAM) system for recognizing fine-grained activities. We exploit the feasibility of using an array of heterogeneous micro-doppler radars to recognize low-level activities. We prototype a short-range and a long-range radar system and evaluate the feasibility of using the system for fine-grained activity recognition. In our evaluation, using real data traces, we show that our system can detect fine-grained user activities with 92.84% accuracy. 
    more » « less
  5. Abstract Advanced Quantitative Precipitation Information (AQPI) is a synergistic project that combines observations and models to improve monitoring and forecasts of precipitation, streamflow, and coastal flooding in the San Francisco Bay Area. As an experimental system, AQPI leverages more than a decade of research, innovation, and implementation of a statewide, state-of-the-art network of observations, and development of the next generation of weather and coastal forecast models. AQPI was developed as a prototype in response to requests from the water management community for improved information on precipitation, riverine, and coastal conditions to inform their decision-making processes. Observation of precipitation in the complex Bay Area landscape of California’s coastal mountain ranges is known to be a challenging problem. But, with new advanced radar network techniques, AQPI is helping fill an important observational gap for this highly populated and vulnerable metropolitan area. The prototype AQPI system consists of improved weather radar data for precipitation estimation; additional surface measurements of precipitation, streamflow, and soil moisture; and a suite of integrated forecast modeling systems to improve situational awareness about current and future water conditions from sky to sea. Together these tools will help improve emergency preparedness and public response to prevent loss of life and destruction of property during extreme storms accompanied by heavy precipitation and high coastal water levels—especially high-moisture laden atmospheric rivers. The Bay Area AQPI system could potentially be replicated in other urban regions in California, the United States, and worldwide. 
    more » « less