Mobile Systems
Mobile devices are the prevalent computing device in many parts of the world, and over the coming years it is expected that mobile Internet usage will outpace desktop usage worldwide. Google is committed to realizing the potential of the mobile web to transform how people interact with computing technology. Google engineers and researchers work on a wide range of problems in mobile computing and networking, including new operating systems and programming platforms (such as Android and ChromeOS); new interaction paradigms between people and devices; advanced wireless communications; and optimizing the web for mobile settings. In addition, many of Google’s core product teams, such as Search, Gmail, and Maps, have groups focused on optimizing the mobile experience, making it faster and more seamless. We take a cross-layer approach to research in mobile systems and networking, cutting across applications, networks, operating systems, and hardware. The tremendous scale of Google’s products and the Android and Chrome platforms make this a very exciting place to work on these problems.
Some representative projects include mobile web performance optimization, new features in Android to greatly reduce network data usage and energy consumption; new platforms for developing high performance web applications on mobile devices; wireless communication protocols that will yield vastly greater performance over today’s standards; and multi-device interaction based on Android, which is now available on a wide variety of consumer electronics.
Recent Publications
Preview abstract
Interactions with Extended Reality Head Mounted Devices (XR HMDs) applications require precise, intuitive and efficient input methods. Current approaches either rely on power-intensive sensors, such as cameras for hand-tracking, or specialized hardware in the form of handheld controllers. As an alternative, past works have explored the use of devices already present with the user, in the form of smartphones and smartwatches as practical input solutions. However, this approach risks interaction overload---how can one determine whether the user’s interaction gestures on the watch-face or phone screen are directed toward control of the mobile device itself or the XR device? To this effect, we propose a novel framework for cross-device input routing and device arbitration by employing Inertial Measurement Units (IMUs) within these devices. We validate our approach in a user study with six participants. By making use of the relative orientation between the headset and the target input device, we can estimate the intended device of interaction with 93.7% accuracy. Our method offers a seamless, energy-efficient alternative for input management in XR, enhancing user experience through natural and ergonomic interactions.
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Preview abstract
We present XDTK, an open-source Unity/Android toolkit for prototyping multi-device interactions in extended reality (XR). With the Unity package and Android app provided in XDTK, data from any number of devices (phones, tablets, or wearables) can be streamed to and surfaced within a Unity-based XR application. ARCore-supported device also provide self-tracked pose data. Devices on the same local network are automatically discovered by the Unity server and their inputs are routed using a custom event framework. We designed XDTK to be modular and easily extendable to enable fast, simple, and effective prototyping of multi-device experiences by both researchers and developers.
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Preview abstract
Keynote at the srsRAN Project Workshop in October 2023: https://srs.io/srsran-project-workshop-october-23-24/
The talk is a summary of the impact that open-source tools and SW radio have had on cellular security research in academia over the last 15 years. It summarizes 2G security research in ~2008-2012 and how the first OSS tools for LTE (openLTE and srsLTE) were a game changer for the field, enabling a tremendous spike in excellent cellular security research work.
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Design Earable Sensing Systems: Perspectives and Lessons Learned from Industry
Trausti Thormundsson
Adjunct Proceedings of the 2023 ACM International Joint Conference on Pervasive and Ubiquitous Computing and the 2023 ACM International Symposium on Wearable Computers, ACM (to appear)
Preview abstract
Earables computing is an emerging research community as the industry witnesses the soaring of True Wireless Stereo (TWS) Active Noise Canceling (ANC) earbuds in the past ten years. There is an increasing trend of newly initiated earable research spanning across mobile health, user-interfaces, speech processing, and context-awareness. Head-worn devices are anticipated to be the next generation Mobile Computing and Human-Computer Interaction (HCI) platform. In this paper, we share our design experiences and lessons learned in building hearable sensing systems from the industry perspective. We also give our takes on future directions of the earable research.
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UE Security Reloaded: Developing a 5G Standalone User-Side Security Testing Framework
Aanjhan Ranganathan
Christina Pöpper
Evangelos Bitsikas
Syed Khandker
16th ACM Conference on Security and Privacy in Wireless and Mobile Networks(2023)
Preview abstract
Security flaws and vulnerabilities in cellular networks directly lead to severe security threats given the data-plane services, from calls to messaging and Internet access, that are involved. While the 5G Standalone (SA) system is currently being deployed worldwide, practical security testing of user equipment has only been conducted for 4G/LTE and earlier network generations. In this paper, we develop and present the first security testing framework for 5G SA user equipment. To that end, we modify the functionality of open-source suites (Open5GS and srsRAN) and develop a broad set of test cases for 5G NAS and RRC layers. We apply our testing framework in a proof-of-concept manner to 5G SA mobile phones, report identified vulnerabilities, and provide detailed insights from our experiments.
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APG: Audioplethysmography for Cardiac Monitoring in Hearables
David Pearl
Rich Howard
Longfei Shangguan
Trausti Thormundsson
MobiCom 2023: The 29th Annual International Conference On Mobile Computing And Networking (MobiCom), Association for Computing Machinery (ACM) (to appear)
Preview abstract
This paper presents Audioplethysmography (APG), a novel cardiac monitoring modality for active noise cancellation (ANC) headphones. APG sends a low intensity ultrasound probing signal using an ANC headphone's speakers and receives the echoes via the on-board feedback microphones. We observed that, as the volume of ear canals slightly changes with blood vessel deformations, the heartbeats will modulate these ultrasound echoes. We built mathematical models to analyze the underlying physics and propose a multi-tone APG signal processing pipeline to derive the heart rate and heart rate variability in both constrained and unconstrained settings. APG enables robust monitoring of cardiac activities using mass-market ANC headphones in the presence of music playback and body motion such as running.
We conducted an eight-month field study with 153 participants to evaluate APG in various conditions. Our studies conform to the (Institutional Review Board) IRB policies from our company. The presented technology, experimental design, and results have been reviewed and further improved by feedback garnered from our internal Health Team, Product Team, User Experience (UX) Team and Legal team. Our results demonstrate that APG achieves consistently high HR (3.21% median error across 153 participants in all scenarios) and HRV (2.70% median error in interbeat interval, IBI) measurement accuracy. Our UX study further shows that APG is resilient to variation in: skin tone, sub-optimal seal conditions, and ear canal size.
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Some of our teams
