Publications (36)
Evaluating Bias in Phoneme-Based Automatic Speech Recognition Systems: An Analysis of IPA Transcription Models
Catherine Bao, Maneesha Rani Saha, Neal Patwari
The popularization of automatic speech recognition (ASR) systems has increased exploration of the demographic biases related to race, age, gender, and accent, often formed from imb…
dRTI: Directional Radio Tomographic Imaging
Bo Wei, Ambuj Varshney, Wen Hu +3
Radio tomographic imaging (RTI) enables device free localisation of people and objects in many challenging environments and situations. Its basic principle is to detect the changes…
Hidden Markov Estimation of Bistatic Range From Cluttered Ultra-wideband Impulse Responses
Merrick McCracken, Neal Patwari
Ultra-wideband (UWB) multistatic radar can be used for target detection and tracking in buildings and rooms. Target detection and tracking relies on accurate knowledge of the bista…
People-Sensing Spatial Characteristics of RF Sensor Networks
Neal Patwari, Joey Wilson
An "RF sensor" network can monitor RSS values on links in the network and perform device-free localization, i.e., locating a person or object moving in the area in which the networ…
Sensing and Stopping Interfering Secondary Users: Validation of an Efficient Spectrum Sharing System
Meles Weldegebriel, Zihan Li, Dustin Maas +3
We present the design and validation of Stoppable Secondary Use (StopSec), a privacy-preserving protocol with the capability to identify a secondary user (SU) causing interference…
Global Performance Disparities Between English-Language Accents in Automatic Speech Recognition
Alex DiChristofano, Henry Shuster, Shefali Chandra +1
Past research has identified discriminatory automatic speech recognition (ASR) performance as a function of the racial group and nationality of the speaker. In this paper, we expan…
RTI Goes Wild: Radio Tomographic Imaging for Outdoor People Detection and Localization
Cesare Alippi, Maurizio Bocca, Giacomo Boracchi +2
RF sensor networks are used to localize people indoor without requiring them to wear invasive electronic devices. These wireless mesh networks, formed by low-power radio transceive…
Detector Based Radio Tomographic Imaging
Hüseyin YiÄitler, Riku Jäntti, Ossi Kaltiokallio +1
Received signal strength based radio tomographic imaging is a popular device-free indoor localization method which reconstructs the spatial loss field of the environment using meas…
Multiple Target Tracking with RF Sensor Networks
Maurizio Bocca, Ossi Kaltiokallio, Neal Patwari +1
RF sensor networks are wireless networks that can localize and track people (or targets) without needing them to carry or wear any electronic device. They use the change in the rec…
Never Use Labels: Signal Strength-Based Bayesian Device-Free Localization in Changing Environments
Peter Hillyard, Neal Patwari
Device-free localization (DFL) methods use measured changes in the received signal strength (RSS) between many pairs of RF nodes to provide location estimates of a person inside th…
Experimental Performance Evaluation of Location Distinction for MIMO Channels
Dustin Maas, Neal Patwari, Daryl Wasden +2
Location distinction is defined as determining whether or not the position of a device has changed. We introduce methods and metrics for performing location distinction in multiple…
Save Our Spectrum: Contact-Free Human Sensing Using Single Carrier Radio
Alemayehu Solomon Abrar, Anh Luong, Peter Hillyard +1
Recent research has demonstrated new capabilities in radio frequency (RF) sensing that apply to health care, smart home, and security applications. However, previous work in RF sen…
Channel Sounding for the Masses: Low Complexity GNU 802.11b Channel Impulse Response Estimation
Mohammad H. Firooz, Dustin Maas, Junxing Zhang +2
New techniques in cross-layer wireless networks are building demand for ubiquitous channel sounding, that is, the capability to measure channel impulse response (CIR) with any stan…
Comparing Respiratory Monitoring Performance of Commercial Wireless Devices
Peter Hillyard, Anh Luong, Alemayehu Solomon Abrar +6
This paper addresses the performance of systems which use commercial wireless devices to make bistatic RF channel measurements for non-contact respiration sensing. Published resear…
Quantifying Interference-Assisted Signal Strength Surveillance of Sound Vibrations
Alemayehu Solomon Abrar, Neal Patwari, Sneha Kumar Kasera
A malicious attacker could, by taking control of internet-of-things devices, use them to capture received signal strength (RSS) measurements and perform surveillance on a person's…
Dial It In: Rotating RF Sensors to Enhance Radio Tomography
Maurizio Bocca, Anh Luong, Neal Patwari +1
A radio tomographic imaging (RTI) system uses the received signal strength (RSS) measured by RF sensors in a static wireless network to localize people in the deployment area, with…
RFI Detection and Identification at OVRO Using Pseudonymetry
Meles Weldegebriel, Zihan Li, Greg Hellbourg +2
Protecting passive radio astronomy observatories from unintended radio-frequency interference (RFI) is increasingly challenging as wireless activity expands near protected bands. W…
A Multi-Scale Spatial Model for RSS-based Device-Free Localization
Ossi Kaltiokallio, Maurizio Bocca, Neal Patwari
RSS-based device-free localization (DFL) monitors changes in the received signal strength (RSS) measured by a network of static wireless nodes to locate people without requiring th…
Monitoring Breathing via Signal Strength in Wireless Networks
Neal Patwari, Joey Wilson, Sai Ananthanarayanan P. R. +2
This paper shows experimentally that standard wireless networks which measure received signal strength (RSS) can be used to reliably detect human breathing and estimate the breathi…
Collision Prediction from UWB Range Measurements
Alemayehu Solomon Abrar, Anh Luong, Gregory Spencer +3
The ability to predict, and thus react to, oncoming collisions among a set of mobile agents is a fundamental requirement for safe autonomous movement, both human and robotic. This…
Joint Ultra-wideband and Signal Strength-based Through-building Tracking for Tactical Operations
Merrick McCracken, Maurizio Bocca, Neal Patwari
Accurate device free localization (DFL) based on received signal strength (RSS) measurements requires placement of radio transceivers on all sides of the target area. Accuracy degr…
Two Measure is Two Know: Calibration-free Full Duplex Monitoring for Software Radio Platforms
Jie Wang, Jonathan Gornet, Alex Orange +5
Future virtualized radio access network (vRAN) infrastructure providers (and today's experimental wireless testbed providers) may be simultaneously uncertain what signals are being…
Breathfinding: A Wireless Network that Monitors and Locates Breathing in a Home
Neal Patwari, Lara Brewer, Quinn Tate +2
This paper explores using RSS measurements on many links in a wireless network to estimate the breathing rate of a person, and the location where the breathing is occurring, in a h…
Sitara: Spectrum Measurement Goes Mobile Through Crowd-sourcing
Phillip Smith, Anh Luong, Shamik Sarkar +5
Software-defined radios (SDRs) are often used in the experimental evaluation of next-generation wireless technologies. While crowd-sourced spectrum monitoring is an important compo…
Through-Wall Person Localization Using Transceivers in Motion
Peter Hillyard, Dustin Maas, Sriram Premnath +2
We develop novel methods for device-free localization (DFL) using transceivers in motion. Such localization technologies are useful in various cross-layer applications/protocols in…
Through-Wall Tracking Using Variance-Based Radio Tomography Networks
Joey Wilson, Neal Patwari
This paper presents a new method for imaging, localizing, and tracking motion behind walls in real-time. The method takes advantage of the motion-induced variance of received signa…
Channel Estimation via Loss Field: Accurate Site-Trained Modeling for Shadowing Prediction
Jie Wang, Meles G. Weldegebriel, Neal Patwari
Future mobile ad hoc networks will share spectrum between many users. Channels will be assigned on the fly to guarantee signal and interference power requirements for requested lin…
Precarity: Modeling the Long Term Effects of Compounded Decisions on Individual Instability
Pegah Nokhiz, Aravinda Kanchana Ruwanpathirana, Neal Patwari +1
When it comes to studying the impacts of decision making, the research has been largely focused on examining the fairness of the decisions, the long-term effects of the decision pi…
Robust Estimators for Variance-Based Device-Free Localization and Tracking
Yang Zhao, Neal Patwari
Human motion in the vicinity of a wireless link causes variations in the link received signal strength (RSS). Device-free localization (DFL) systems, such as variance-based radio t…
Quantifying an Interference-Assisted Signal Strength Breathing Surveillance Attack
Alemayehu Solomon Abrar, Neal Patwari, Aniqua Baset +1
A malicious attacker could, by taking control of internet-of-things devices, use them to capture received signal strength (RSS) measurements and perform surveillance on a person's…
RSS Models for Respiration Rate Monitoring
Hüseyin YiÄitler, Ossi Kaltiokallio, Roland Hostettler +3
Received signal strength based respiration rate monitoring is emerging as an alternative non-contact technology. These systems make use of the radio measurements of short-range com…
Through Wall People Localization Exploiting Radio Windows
Arijit Banerjee, Dustin Maas, Maurizio Bocca +2
We introduce and investigate the ability of an attacker to surreptitiously use an otherwise secure wireless network to detect moving people through walls, in an area in which peopl…
EpiFi: An In-Home Sensor Network Architecture for Epidemiological Studies
Philip Lundrigan, Kyeong Min, Neal Patwari +8
We design and build a system called EpiFi, which allows epidemiologists to easily design and deploy experiments in homes. The focus of EpiFi is reducing the barrier to entry for de…
Correlated Link Shadow Fading in Multi-hop Wireless Networks
Piyush Agrawal, Neal Patwari
Accurate representation of the physical layer is required for analysis and simulation of multi-hop networking in sensor, ad hoc, and mesh networks. This paper investigates, models,…
Racial Disparities in Pulse Oximetry Cannot Be Fixed With Race-Based Correction
Neal Patwari, Di Huang, Kiki Bonetta-Misteli
Studies have shown pulse oximeter measurements of blood oxygenation have statistical bias that is a function of race, which results in higher rates of occult hypoxemia, i.e., misse…
Catch a Breath: Non-invasive Respiration Rate Monitoring via Wireless Communication
Ossi Kaltiokallio, Hüseyin Yigitler, Riku Jäntti +1
Radio signals are sensitive to changes in the environment, which for example is reflected on the received signal strength (RSS) measurements of low-cost wireless devices. This info…