Science Daily January 10, 2020 A team of researchers in the US (Industry, UC Davis, Cornell University) has discovered two alternative 4-satellite constellations with 24- and 48-hour periods, both of which attain nearly continuous global coverage. They harness energy from nonlinear orbital perturbation forces (e.g., Earth’s geopotential, gravitational effects of the sun and moon, and solar radiation pressure) to reduce their propellant and maintenance costs. The 24-hour period constellation reduces the overall required vehicle mass budget for propellant by approximately 60% compared to a geostationary Earth orbit constellation with similar coverage over typical satellite lifetimes. The discovery could drive advances […]
Category Archives: Communications technology
Soundwaves carry information between quantum systems
Nanowerk December 30, 2019 An international team of researchers ( USA- University of Chicago, UC Santa Barbara, Argonne National Laboratory, Japan) created a hybrid quantum system that acoustically drives transitions in electron spins. The experiment showed a basis for mechanical (strain) control. They developed a theoretical model from a combination of direct experimental observation and density functional theory calculations. From all of this information, they illustrated different types of mechanical strain that drive longer-lasting spins. The material studied was silicon carbide, which has been shown recently to support long-lived spin states that can be accessed optically. The results offer theoretical […]
New system transmits high-speed unrepeated signal over 520 kilometers
EurekAlert December 16, 2019 To make long-haul data transmission cheaper an international team of researchers (Russia, USA industry) developed transmission line with three sections, each consisting of fiber optic cables of two types connected in series. Remote optically pumped erbium amplifiers (ROPA) were installed at the points of junction between the sections. The systems amplify the signal along the link without the need for electrical power sources. They successfully transmitted a signal over 520 km (323 mi) at 200 Gbps. To avoid the attenuation of the signal, it was amplified initially upon transmission and then two more times remotely, along […]
Communications device offers huge bandwidth potential
EurekAlert December 10, 2019 Researchers at the University of Illinois have demonstrated that the device they developed can rapidly switch functionality to perform the varied tasks needed to support a network with carrier frequencies of over 100 gigahertz. They developed a 3D-printed scaffold, which served as a negative of the desired network. A polymer was poured in and, once set, microcapillaries 0.3 millimeters in diameter were filled with plasma, metal or a dielectric gas. Using this replica-molding technique they perfected the dimensions and spacings of the microcapillaries in the lattice. They showed that rapid changes in the electromagnetic characteristics of […]
Structured light promises path to faster, more secure communications
Eurekalert November 5, 2019 Researchers in South Africa review the progress being made in using structured light in quantum protocols to create a larger encoding alphabet, stronger security and better resistance to noise. Since patterns of light can be distinguished from each other, they can be used as a form of alphabet. Its information capacity is much higher than polarized light and security is stronger, and the robustness to noise is improved. It turns out that many protocols can be efficiently implemented withotterns of light. Unfortunately, the toolkit to manage these patterns is still underdeveloped and requires a lot of […]
First Demonstration of a 1 Petabit per Second Network Node
National Institute of Information and Communications Technology, October 17, 2019 Researchers in Japan have successfully implemented a network demonstration using state-of-the-art large-scale spatial optical switching, aiming at petabit-class next-generation optical networks using spatial-division multiplexing. The testbed supported data rates from 10 Terabit per second up to 1 Petabit per second over 3 types of next-generation multicore fibers and included practical requirements of real networks, such as protection switching. The total capacity of the network was 1 Petabit per second. The system was demonstrated in 4 fundamental scenarios that constitute the building blocks of the next-generation optical fiber networks…read more.
How big ideas can change the world: the revolutionary potential of LiFi
Physics World October 22, 2019 Researchers at the University of Oxford have shown that LiFi can work in lab demonstrations at speeds of 224 Gbps, illustrating the huge progress since Professor Haas from the University of Edinburgh, introduced LiFi in his 2011 TED talk. In that presentation, Haas demonstrated the benefits of LiFi with an LED light bulb housed in a desk lamp sitting on a small receiver unit. The four fundamental challenges that LiFi addresses are – first it’s efficient, second, LED lights are widely available, third, LiFi offers high capacity (the visible spectrum is 10,000 times wider than […]
A mathematical model reveals long-distance cell communication mechanism
Science Daily October 15, 2019 Cells often communicate using signaling molecules, which can travel only a short distance. Nevertheless, the cells can also communicate over large distances to spur collective action. An international team of researchers (USA – UT Houston, South Korea) used an engineered transcriptional circuit of combined positive and negative feedback loops in E. coli, which can periodically release two types of signaling molecules: activator and repressor. As the signaling molecules travel over a short distance, cells can only talk to their nearest neighbors. However, cell communities synchronize oscillatory gene expression in spatially extended systems if the transcriptional […]
Development of highly sensitive diode, converts microwaves to electricity
Science Daily September 26, 2019 Researchers in Japan have developed a highly sensitive rectifying element in the form of a nanowire backward diode, which can covert low-power microwaves into electricity. Equipment they used consists of a radio wave power generating element. The technology can efficiently convert 100nW-class low-power radio waves into electricity, enabling the conversion of microwaves emitted into the environment from mobile phone base stations in an area that is over 10 times greater than was previously possible. The researchers expect that the nanowire backward diode will be applied in using plentiful ambient radio wave energy in 5G communications, […]
Researchers show atoms can receive common communications signals
Nanowerk September 5, 2019 Researchers at NIST team used cesium atoms to receive digital bits in the most common communications format, which is used in cell phones, Wi-Fi and satellite TV, to demonstrate one can use atoms to receive modulated signals. The method works across a huge range of frequencies. They used a recently developed atom-based mixer to convert input signals into new frequencies. One RF signal acts as a reference and a second RF signal serves as the modulated signal carrier. Differences in frequency and the offset between the two signals were detected and measured by probing the atoms. […]