Li Sun, Souvik Sen, Dimitrios Koutsonikolas, Kyu-Han Kim
{"title":"WiDraw: Enabling Hands-free Drawing in the Air on Commodity WiFi Devices","authors":"Li Sun, Souvik Sen, Dimitrios Koutsonikolas, Kyu-Han Kim","doi":"10.1145/2789168.2790129","DOIUrl":"https://doi.org/10.1145/2789168.2790129","url":null,"abstract":"This paper demonstrates that it is possible to leverage WiFi signals from commodity mobile devices to enable hands-free drawing in the air. While prior solutions require the user to hold a wireless transmitter, or require custom wireless hardware, or can only determine a pre-defined set of hand gestures, this paper introduces WiDraw, the first hand motion tracking system using commodity WiFi cards, and without any user wearables. WiDraw harnesses the Angle-of-Arrival values of incoming wireless signals at the mobile device to track the user's hand trajectory. We utilize the intuition that whenever the user's hand occludes a signal coming from a certain direction, the signal strength of the angle representing the same direction will experience a drop. Our software prototype using commodity wireless cards can track the user's hand with a median error lower than 5 cm. We use WiDraw to implement an in-air handwriting application that allows the user to draw letters, words, and sentences, and achieves a mean word recognition accuracy of 91%.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127558722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Agility and Fragility in a Real-time World","authors":"Gilles Grapinet","doi":"10.1145/2789168.2790090","DOIUrl":"https://doi.org/10.1145/2789168.2790090","url":null,"abstract":"Connected mobile devices have now reached the age of being perceived as a commodity. Users expect to be able to enjoy the same level of service and performance both on the go and at home. A new wave of cloud-supported services brought about by the integration of machine learning in consumer electronics –such as Smart watches, NEST sensors, and Self-Driving cars –is entering the market with a disruptive power. The Internet of Everything is already on our wrists, cars, buildings, and pockets, and is pushing through new economic models (such as Shared Economy or Data Economy). Current technology is struggling to meet the demands posed by new applications and services; specifically, it lacks the agility needed to adapt to fast-changing business models and technical requirements; it also comes with fragilities as most of our current infrastructures, systems and solutions were not designed to allow massive usage of real-time applications at personal level. Security, connectivity, mobility, latency, and scalability are just some of the many challenges that pave the way towards a seamless user experience. Device-todevice communications along with new business and trust models will dominate the Internet. It is essential for the Internet of Everything to succeed, and that industry, government and academia join forces to build brand new protocol architectures, computing paradigms, and regulatory frameworks designed to support mobility, high performance services, strong security and a fine user privacy granularity adapted to an expanding level of personal data dissemination.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"59 33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128186944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Theodore Stoner, Xuetao Wei, Joseph Knight, Lei Guo
{"title":"Experience: Rethinking RRC State Machine Optimization in Light of Recent Advancements","authors":"Theodore Stoner, Xuetao Wei, Joseph Knight, Lei Guo","doi":"10.1145/2789168.2790105","DOIUrl":"https://doi.org/10.1145/2789168.2790105","url":null,"abstract":"Broadband mobile networks utilize a radio resource control (RRC) state machine to allocate scarce radio resources. Current implementations introduce high latencies and cross-layer degradation. Recently, the RRC enhancements, continuous packet connectivity (CPC) and the enhanced forward access channel (Enhanced FACH), have emerged in UMTS. We study the availability and performance of these enhancements on a network serving a market with a population in the millions. Our experience in the wild shows these enhancements offer significant reductions in latency, mobile device energy consumption, and improved end user experience. We develop new over-the-air measurements that resolve existing limitations in measuring RRC parameters. We find CPC provides significant benefits with minimal resource costs, prompting us to rethink past optimization strategies. We examine the cross-layer performance of CPC and Enhanced FACH, concluding that CPC provides reductions in mobile device energy consumption for many applications. While the performance increase of HS-FACH is substantial, cross-layer performance is limited by the legacy uplink random access channel (RACH), and we conclude full support of Enhanced FACH is necessary to benefit most applications. Given that UMTS growth will exceed LTE for several more years and the greater worldwide deployment of UMTS, our quantitative results should be of great interest to network operators adding capacity to these networks. Finally, these results provide new insights for application developers wishing to optimize performance with these RRC enhancements.","PeriodicalId":424497,"journal":{"name":"Proceedings of the 21st Annual International Conference on Mobile Computing and Networking","volume":"207 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121864666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}