Science Daily October 9, 2018 Researchers at the US Army Research Laboratory have developed a technique for determining DoA of a radio frequency signal source based on an algorithm that statistically models the received signal strength (RSS) gradient and controls for spatial outliers and correlations. When the signal is extremely noisy, the estimator correctly outputs that no DoA is present and the output is an estimated DoA and associated uncertainty. The technique works in conditions of heavy multipath, does not require any fixed infrastructure, does not rely on prior training data, knowledge about the environment, multiple antennas, or prior calibration […]
Category Archives: Sensors
New laser technology can identify unknown white powders from safe distance
Phys.org October 8, 2018 An international team of researchers (UK, USA – industry) was able to identify 11 white powder samples using their infrared laser system. No samples or disturbance of the powders were required, and they could be identified from up to one metre away. They illuminated each sample with broadband coherent light in the 8–9-µm band. Similarities between different spectra were quantified using Pearson’s correlation coefficient, confirming that spectral features in the 8–9-µm wavelength region were sufficient to discriminate between all eleven powders evaluated in the study. The researchers believe that the identification system will prove most useful […]
Possible game changer in detection of submarines
Next Big Future October 9, 2018 Researchers in China are working on a device they hope will be able to reveal the location of a target as far as 500 metres below the ocean surface monitoring tiny disturbances in the Earth’s magnetic field caused by metallic objects such as submarines. They are also working on sensors using cutting-edge quantum technology to chase the gravitational abnormality that a submarine creates in a large body of water. Powerful listening devices have also been planted in strategic seabed near the American naval base in Guam and in the South China Sea, some of […]
Crowd counting through walls with WiFi (w/video)
Science Daily September 24, 2018 Researchers at UC Santa Barbara propose a framework to sense occupancy attributes of an area, such as speed of a crowd traversing through the area, the total number of people in the area, and the rate of arrival of people into the area, using only the received power measurements (RSSI) of two WiFi links. They developed a mathematical model to relate these parameters to the occupancy attributes of interest. They tested the technology in different locations, with different wall properties and with several different numbers of people — up to and including 20. They showed a counting […]
‘Papertronics’ could fold, biodegrade and be the basis for the next generation of devices
Nanowerk September 21, 2018 Researchers at the State University of New York‐Binghamton have developed a bacteria‐powered battery by building microbial fuel cells with inactive, lyophilized exoelectrogenic cells which generates power within minutes of adding saliva. An oxygen‐tight interface and engineered conductive paper reservoir boosts microbial electron transfer efficiency. Exoelectrogenic bacteria preinoculated in the paper battery is freeze‐dried for long‐term storage and can be readily rehydrated for on‐demand power generation. Sixteen microbial fuel cells are incorporated on a single sheet of paper while all are connected in series with two electrical switches mounted on a paper circuit board, produced more than […]
Perovskite semiconductors seeing right through next generation X-ray detectors
Phys.org September 21, 2018 An international team of researchers (Austria, Switzerland, Germany, South Korea, Belgium, China, India) has designed a direct X-ray detector based on halide perovskite semiconductor (Cs2AgBiBr6) which has high sensitivity and structural stability. By optimising the materials and lowering the operating temperature they were even able to improve the X-ray sensitivity of the device tenfold, ultimately peaking near 500 times more sensitive than commercial direct conversion X-ray detectors on the market. The finding has applications as a diagnostic tool in fundamental research and medical fields… read more. TECHNICAL ARTICLE 1 , 2 , 3 , 4 ,
Spray-on antennas could unlock potential of smart, connected technology
Nanowerk September 21, 2018 Researchers at Drexel University developed a method for spraying invisibly thin antennas, made from MXene (titanium carbide), a two-dimensional, metallic material. It is stronger than metals, metallically conductive and can be dissolved in water to create an ink or paint. The exceptional conductivity of the material enables it to transmit and direct radio waves, even when it’s applied in a very thin coating. Even transparent antennas with thicknesses of tens of nanometers were able to communicate efficiently. By increasing the thickness up to 8 microns, the performance of MXene antenna achieved 98 percent of its predicted […]
Enabling ‘internet of photonic things’ with miniature sensors
Science Daily September 12, 2018 In IoT there are vast numbers of spatially distributed wireless sensors predominately based on electronics which are often are hampered by electromagnetic interference. Researchers at Washington University developed whispering gallery mode (WGM) sensors resonating at light frequencies and at vibrational or mechanical frequencies. The 127 mm by 67 mm mainboard of the WGM sensor integrates the entire architecture of the sensor system. The sensor, made of glass, is connected to the mainboard by a single optical fiber. A laser light is used to probe a WGM sensor. Light coupled out of the sensor is sent […]
Regular old WiFi spots dangerous objects in bags
Futurity August 16, 2018 A team of researchers in the US (Rutgers University, Indiana University, Binghamton University) have developed a system which detects the existence of suspicious objects and identifies the material type based on the reconstructed CSI complex value (including both amplitude and phase information); it then determines the risk level of the object by examining the object’s dimension (i.e., liquid volume and metal object’s shape) based on the reconstructed CSI complex of the signals reflected by the object. In tests the system was able to detect over 95% suspicious objects in different types of bags and successfully identify […]
Uncovering the interplay between two famous quantum effects
Phys.org July 23, 2018 According to some physicists the next scientific breakthroughs could lie in the interplay between Casimir force and superconductivity. Researchers in the Netherlands developed a sensor that consists of a microchip on which two strings are placed in close proximity. The wires can be cooled down to cryogenic temperatures, making them superconducting. The strings have holes in the centre that act as an optical resonator trapping laser light of a certain wavelength. They used this light to measure small displacements between the two wires, in essence it is possible to measure the forces that are acting upon […]