MOBICOM

With the continuous growth of the Internet of Things (IoT), the trend of increasing numbers of IoT devices will continue. To increase the network's capability to support a large number of active devices accessing a network concurrently, this work ...

Next generation wireless networks embrace mmWave technology for its high capacity. Yet, mmWave radios bear a fundamental coverage limitation due to the high directionality and propagation artifacts. In this paper, we explore an economical paradigm based ...

WiFi is the de facto standard for providing wireless access to the Internet using the 2.4GHz ISM band. Tens of billions of WiFi devices were shipped worldwide and WiFi Access Points (APs) are ubiquitous in public, enterprise and personal environments. ...

Unlicensed LPWANs on ISM bands share the spectrum with various wireless techniques, such as Wi-Fi, Bluetooth, and ZigBee. The explosion of IoT deployments calls for an increasing need for long-range cross-technology communication (CTC) between LPWANs ...

Phased array beamforming has been extensively explored as a physical layer primitive to improve the secrecy capacity of wireless communication links. However, existing solutions are incompatible with low-profile IoT devices due to cost, power and form ...

Commercial Internet of Things (IoT) deployments are mostly closed-source systems that offer little to no flexibility to modify the hardware and software of the end devices. Once deployed, retrofitting such systems to an upgraded functionality requires ...

We report our experiences of developing, deploying, and evaluating MLoc, a smartphone-based indoor localization system for malls. MLoc uses Bluetooth Low Energy RSSI and geomagnetic field strength as fingerprints. We develop efficient approaches for ...

This paper presents our experience in adopting recent research results of mobile phone based indoor/outdoor detection (IODetector) to support the real world business of on-demand food delivery. The real world deployment of the adopted IODetector ...

Camera tracking has become a key technology for various application scenarios, especially for AR-based camera-to-screen interaction. Demand for subtle motion detection in camera tracking makes it essential to explore the six degrees of freedom (6-DoF) ...

The spectrum above 100 GHz has the potential to enable accurate 3D wireless localization due to the large swath of available spectrum. Yet, existing wide-band localization systems utilize the time of arrival measurements requiring strict time ...

Infrastructure-assisted autonomous driving is an emerging paradigm that expects to significantly improve the driving safety of autonomous vehicles. The key enabling technology for this vision is to fuse LiDAR results from the roadside infrastructure and ...

While GPS-based outdoor localization has become a norm, very few indoor localization systems have been deployed and used. In this paper, we share our 5-year experience on the design, development and evaluation of a large-scale WiFi indoor localization ...

Federated learning (FL) is an emerging distributed machine learning (ML) paradigm with enhanced privacy, aiming to achieve a "good" ML model for as many as participants while consuming as little as wall clock time. By executing across thousands or even ...

Optical camera communication (OCC) enabled by LED and embedded cameras has attracted extensive attention, thanks to its rich spectrum availability and ready deployability. However, the close interactions between OCC and the indoor spaces have created ...

Convolutional neural networks (CNNs) play an important role in today's mobile and edge computing systems for vision-based tasks like object classification and detection. However, state-of-the-art methods on CNN acceleration are trapped in either limited ...

With the wide adoption of AI applications, there is a pressing need of enabling real-time neural network (NN) inference on small embedded devices, but deploying NNs and achieving high performance of NN inference on these small devices is challenging due ...

This paper proposes Mandheling, the first system that enables highly resource-efficient on-device training by orchestrating mixed-precision training with on-chip Digital Signal Processor (DSP) offloading. Mandheling fully explores the advantages of DSP ...

Mobile-centric AI applications put forward high requirements for resource-efficiency of model inference. Input filtering is a promising approach to eliminate the redundancy in the input so as to reduce the cost of inference. Previous efforts have ...

In this paper, we propose CoMEt, a radio frequency based approach that measures soil moisture at multiple depths underneath the ground surface without installing any objects in the soil and without making any contact with the ground surface. The main ...

In this paper, we are interested in high-quality imaging of still objects with only received power measurements of off-the-shelf WiFi transceivers. We show that the scattered WiFi signals off of objects carry much richer information about the edges of ...

Besides the conventional communication function, wireless signals are actively exploited for sensing purposes recently. However, a missing component of existing wireless sensing is sensing under device motions. This is challenging because device motions ...

The major obstacle for learning-based RF sensing is to obtain a high-quality large-scale annotated dataset. However, unlike visual datasets that can be easily annotated by human workers, RF signal is non-intuitive and non-interpretable, which causes the ...

The existing RF-based liquid identification methods commonly require a training network of liquid or the container information, such as material and width. Moreover, status quo methods are inapplicable when the solution height is lower than that of the ...

Face authentication (FA) schemes are universally adopted. However, current FA systems are mainly camera-based and hence susceptible to face occlusion (e.g., facial masks) and vulnerable to spoofing attacks (e.g., 3D-printed masks). This paper exploits ...

Human activity recognition (HAR) is a key enabling technology for a wide range of emerging applications. Although multimodal sensing systems are essential for capturing complex and dynamic human activities in real-world settings, they bring several new ...

Earpiece mode of smartphones is often used for confidential communication. In this paper, we proposed a remote(>2m) and motion-resilient attack on smartphone earpiece. We developed an end-to-end eavesdropping system mmEve based on a commercial mmWave ...

In this paper, we present a low-maintenance, wind-powered, battery-free, biocompatible, tree wearable, and intelligent sensing system, namely IoTree, to monitor water and nutrient levels inside a living tree. IoTree system includes tiny-size, ...

We describe a study conducted at a large public university campus in the United States which shows the efficacy of network log information for digital contact tracing and prediction of COVID-19 cases. Over the period of January 18, 2021 to May 7, 2021, ...

Acoustic sensing shows great potential to transform billions of consumer-grade electronic devices that people interact with on a daily basis into ubiquitous sensing platforms. In this paper, we share our experience and findings during the process of ...

Magnetic sensing is emerging as an enabling technology for various engaging applications. Representative use cases include high-accuracy posture tracking, human-machine interaction, and haptic sensing. This technology uses multiple MEMS magnetometers to ...