Pages: pp. 15-17
A Switzerland-based semiconductor vendor has developed a system for mobile devices that determines a user's location when neither GPS nor Wi-Fi is available. This could be valuable for users inside buildings in crowded urban downtown areas or in mountainous or heavily forested regions.
STMicroelectronics' system starts by taking input from three small, high-performance microelectromechanical systems, each on its own chip: a gyroscope, a compass-like sensor that measures the Earth's magnetic fields, and a sensor that estimates the user's altitude based on air-pressure readings.
Using multiple sensors provides enhanced motion- and location-based capabilities, said Benedetto Vigna, group vice president and general manager of STMicroelectronics' MEMS, Sensors, and High-Performance Analog Division.
The product employs a dedicated processor, along with STMicroelectronics' iNEMO filtering and predictive software engine, to integrate the different types of location-based information. It then utilizes dead reckoning to calculate users' positions in three dimensions (including altitude).
The technology yields information on users' linear acceleration, angular velocity, heading, and altitude. This enables them to identify the direction in which they're heading and their location.
According to STMicroelectronics, the system was designed to be energy-efficient, an important factor for battery-powered smartphones and other mobile devices.
The geomagnetic module—which measures 3 × 5 × 1 mm—offers high-resolution, three-axis sensing of linear and magnetic motion.
The 3-axis digital gyroscope measures 4 × 4 × 1 mm and doesn't require continuous communication between the sensor and the host processor, which reduces power consumption.
The air-pressure sensor measures 3 × 3 × 1 mm, operates at between 700 meters below and 10,000 m above sea level, and can recognize altitude changes as small as 0.3 m.
A virus has infected the system behind American Predator and Reaper military drones.
Initially, US Air Force officials expressed fear the virus could log the keystrokes of the aircraft's remote pilots, creating the possibility that hackers could obtain and sell or otherwise distribute classified information.
However, military cybersecurity specialists now explain, the virus was a common type of malware that steals online gaming logins and passwords. Thus, they say, the malware probably wasn't part of an attack targeting the drones. Instead, it may have worked its way from other systems onto the US Department of Defense (DoD) networks.
Figure STMicroelectronics has developed a product that uses three chip-based systems—a gyroscope, a compass-like sensor that measures the Earth's magnetic fields, and a sensor that estimates the user's altitude based on air-pressure readings—to determine a mobile-device user's location.
Air Force officials noted that the malware infected ground systems that are separate from the drones' flight controls and did not affect their operations. Thus, even after the virus was found, pilots continued to fly the drones, which the US military has used frequently in Afghanistan and Iraq.
The DoD's Host-Based Security System—a COTS-based application designed to monitor, detect, and counter known cyberthreats—found the malware recently.
Officials said that despite numerous efforts, they couldn't remove it from the computers at Creech Air Force Base in Nevada that control the aircraft. Instead, they had had to erase and reformat the drives that the drones' control systems use, a time-consuming process.
The malware incident isn't the drones' first identified security problem. For example, many of the aircraft don't encrypt the video they transmit to US forces. In 2009, soldiers found hours of footage shot by drones on the laptops of captured Iraqi insurgents.
Supposedly, the drones' cockpits are not connected to the Internet, which should make them unable to transmit captured keystrokes to a hacker and leave them immune from transmitted malware. In the past, though, the use of external storage drives has introduced problems to military networks.
Several years ago, experts say a worm infected Predator and Reaper drones via the removable hard drives that load map updates and transport-mission videos from one computer to another. The DoD has ordered all drone units to stop using the drives.
Rice University researchers say they've developed a full-duplex wireless technology that could double network throughput inexpensively without requiring new hardware for devices or networks and without causing service interruptions.
Currently, mobile networks require devices to use different frequencies to send and receive data. Full-duplex technology lets mobile devices send and receive data on the same frequency, effectively doubling a network's capacity.
The Rice scientists—led by Ashutosh Sabharwal, associate professor of electrical and computer engineering—demonstrated that device makers could reliably add full-duplex to existing smartphones and still maintain signal quality.
The researchers added full-duplex as an additional mode to the existing hardware, meaning that device makers wouldn't be required to add new hardware.
Said Sabharwal, "Device makers love this because real estate inside mobile devices is at a premium."
In the past, the concern with using the same frequency to send and receive data was that the dual sets of transmissions would interfere with accurate reception of incoming signals.
The Rice researchers overcame this by repurposing an existing antenna that devices currently utilize for multiple-input, multiple-output technology. MIMO uses several transmitters and receivers, rather than just one of each, to increase wireless throughput. With MIMO, multiple signals that the Rice system transmits cancel each other out, enabling the recipient to accurately receive what's being sent.
Sabharwal said his team will add the full-duplex technology into its wireless open access research platform, which is available to other scientists.
Although full-duplex wireless technology doesn't necessitate new cell towers, it would require new industry standards.
Thus, the researchers say, it probably won't appear for several years, when carriers begin using fifth-generation cellular technology. Major carriers are just beginning to roll out 4G networks.
The researchers say their work already has attracted the attention of wireless providers worldwide.
The Rice scientists also showed that full-duplex systems could operate in asynchronous mode, meaning that a node could begin to receive one signal while still transmitting another, further increasing throughput.
Japanese researchers have developed a pedestrian navigation system that uses haptics so that users can watch where they're going and not have to look at maps or a navigational device. They say their Hapmap system could be particularly useful for the visually impaired.
Keio University and University of Tokyo scientists developed Hapmap, which provides subtle, complex cues that accurately let users follow a winding path's curves without having to watch the small, battery-powered device.
Typically, pedestrian navigation systems are limited to simple cues such as "walk straight ahead," even if a pathway has many curves.
Hapmap's haptic output com-ponent, operated by a servo motor, resembles a small seesaw, which pushes into a user's hand. When the display tilts right or left, it tells the pedestrian to walk in the indicated direction. When the display doesn't tilt, the user walks straight ahead. The researchers say this gives users the sensation of holding onto a railing that is guiding them along a path.
Hapmap includes a user-tracking system and motion-capture cameras to identify where the pedestrian is and which way a path is turning. This enables the system to automatically control the haptic feedback in real time and offer accurate, detailed navigational information.
In the future, the researchers hope to enable Hapmap use in conjunction with GPS and other navigation systems.
Academic researchers have developed a system designed to prevent hackers from attacking implantable electronic medical devices such as heart pacemakers.
MIT and University of Massa-chusetts Amherst scientists say their system would keep hackers from being able to affect an implantable device's operations or steal patient information.
They note that implanted devices such as pacemakers, defibrillators, and insulin pumps increasingly include wireless communication capabilities, used for purposes such as remote monitoring and diagnosis.
Research has shown that it might be possible to exploit the wireless capabilities to send commands to a device or intercept data that it transmits, although no such incidents have been reported.
The scientists developed a transmitter they call a shield, which patients could wear around their neck or wrist. The shield relays messages between an implanted device and authorized endpoints. It uses techniques such as signal jamming and encrypted channels to secure the communications and thereby block the interception of messages and the issuance of commands.
The researchers noted that the eventual commercial success of their technology would depend in part on how serious patients consider the threat of attack against their implanted devices.
University of Washington scientists have built a transistor that uses protons to send information, potentially allowing the creation of devices that could communicate with living things. Such devices could monitor biological processes and eventually transmit signals that could control various functions.
Researchers are interested in using devices that can work directly with, for example, the human body, to help enable biological sensing or more effective prosthetics.
Electronic devices transmit information using electrons. Living things, on the other hand, use ions, which are positively or negatively charged atoms. Protons are positively charged hydrogen ions.
The challenge is finding a way to translate electronic signals into ionic and protonic ones and vice versa, noted assistant professor Marco Rolandi, the project's lead researcher.
"We found a biomaterial that is very good at conducting protons and allows the potential for interfacing with living systems," Rolandi said.
The University of Washington researchers developed a 5-micron-wide field-effect transistor that sends pulses of proton current.
"In our device, large bioinspired molecules can move protons, and a proton current can be switched on and off in a way that's completely analogous to an electronic current in any other field-effect transistor," Rolandi explained.
The device is made with maleic-chitosan, a substance typically obtained commercially from chitin, the structural element in crustaceans' external skeletons. According to the researchers, the material is easily obtained, simple to work with, and compatible with living tissue.
They also note that chitosan absorbs water and forms multiple hydrogen bonds within a transistor over which protons can easily hop.
The current prototype has a silicon base and thus couldn't be placed into a human body. However, the use of a biocompatible base could enable such implantation in the distant future.
Figure University of Washington researchers have developed a protonic field-effect transistor (a) that uses protons to send information, which potentially allows the creation of devices that could communicate with living things. In the transistor, a voltage applied between the proton-transparent palladium hydride (PdHx) source and drain initiates a protonic-current flow along the maleic-chitosan channel, shown in yellow. When hydrated, maleic-chitosan nanofibers (b) form an extended hydrogen bond network along which protons hop. An electrostatic potential applied to the gate electrode turns the protonic current on or off.