Human antenna: A person’s body can direct stray electromagnetic radiation in the environment.
Source: “Your Noise Is My Command: Sensing Gestures Using the Body as an Antenna”
Gabe Cohn et al.
Proceedings of the CHI Conference on Human Factors in Computing Systems, Vancouver, British Columbia, May 7-12, 2011
Results: Researchers at Microsoft and the University of Washington demonstrated that the human body can be used as an antenna to direct electromagnetic “noise,” or ambient radiation—in this case from wiring in a wall. The resulting signal could be used to control a gesture-based interface.
Why it matters: Gesture-based interfaces such as the Nintendo Wii and the Microsoft Kinect have transformed gaming. The new work, which represents a novel way to measure gestures, could make such interfaces less expensive and easier to install. The system could use electromagnetic radiation from home appliances and mobile-phone signals as well as from home wiring.
Methods: The system is designed to pick up signals produced by interactions between the human body and objects that give off electromagnetic radiation. To capture those signals, the researchers had test subjects wear a grounding strap, a bracelet normally used to keep static electricity from building up in the body. In this case, the grounding strap detected the change in electromagnetic radiation in the body. The energy was directed to a connected analog-to-digital converter, to change the signal into a form that could be fed to a laptop; the laptop ran it through algorithms designed to determine the person’s location within a house and orientation with respect to the wall. To control a gestural interface, the system will first have to be trained to recognize the normal landscape of electromagnetic radiation and detect any changes. Systems like the Kinect require a similar type of spatial training.
Next Steps: The researchers want to make the system smaller and more portable. For example, instead of using a laptop to collect and process the gestural data, they’d like to be able to use a phone or watch. They’d also like to be able to analyze the data in real time.
A Processor for Apps
Custom design could extend smart-phone battery life How to turn the body into a functional antenna.
Source: “Greendroid: Exploring the Next Evolution in Smartphone Application Processors”
Steven Swanson and Michael Bedford Taylor
IEEE Communications (4): 112-119
Results: Researchers at the University of California, San Diego, proposed a chip design that is specialized for Android mobile devices. They showed that the chip could be 11 times as energy efficient as a conventional mobile processor in running Google’s Android mobile operating system and popular apps.
Why it matters: The capabilities of smart phones and other mobile computing devices are limited by the capacity of their batteries. For decades, computer processors have steadily gotten faster while their power consumption has stayed the same, but transistors are now so small that they cannot be operated faster or packed more densely onto a chip without an increase in power use. New ways to make mobile chips more efficient must be found if mobile devices are to continue gaining computing ability and taking on new functions.
Methods: To make the chips, software was used to record the computational tasks a phone faced when running popular apps for e-mail, maps, video, and the Web radio service Pandora, among others. A tool developed by the researchers then translated the most commonly used code from those apps into specialized physical circuits to be added to the chip design. Those circuits closely mimic the information processing specified by the app code, enabling the chip to perform its most common tasks much more efficiently than a general-purpose computer processor.
Next Steps: The researchers have partnered with chip manufacturer Global Foundries to produce a physical proof-of-concept prototype, which is expected to be ready by late summer. The prototype chip will use transistors smaller than those currently on the market, with feature sizes as small as 28 nanometers. (The most advanced chips available today have 32-nanometer features.) It will be installed in a prototype mobile device running a real operating system and apps so that its energy efficiency can be compared with that of conventional chips. A second prototype chip designed to handle a wider range of Android applications is expected to be ready by the middle of next year.Measuring Gestures