DARPA August 10, 2022 DARPA has selected 11 teams, from academia and large and small commercial companies, for Phase 1 of the Space-Based Adaptive Communications Node program, known as Space-BACN. Space-BACN aims to create a low-cost, reconfigurable optical communications terminal that adapts to most optical intersatellite link standards, translating between diverse satellite constellations. It would create an “internet” of low-Earth orbit (LEO) satellites, enabling seamless communication between military/government and commercial/civil satellite constellations that currently are unable to talk with each other. Phase 1 of Space- BACN spans 14 months and will conclude with a preliminary design review for the first […]
Category Archives: Communications technology
Magnetic superstructures as a promising material for 6G technology
Phys.org June 20, 2022 A chiral spin soliton lattice (CSL) exhibits reconfigurability in periodicity over a macroscopic length scale. Such coherent and tunable characteristics of the CSL lead to an emergence of elementary excitation of the CSL and bring a controllability of the dispersion relation of the CSL phonon. An international team of researchers (Japan, Canada, Russia, Germany) used a broadband microwave spectroscopy technique, and directly found that higher-order magnetic resonance modes appear in the CSL phase of a chiral helimagnet CrNb3S6, which is ascribed to the CSL phonon response. The resonance frequency of the CSL phonon can be tuned […]
Researchers demonstrate 40-channel optical communication link, capable of transmitting 400 GB of data per second
Phys.org June 9, 2022 A team of researchers in the US (University of Central Florida, NIST, Stanford University, University of Pennsylvania) has experimentally demonstrated a 400 Gbit/s optical communication link utilizing wavelength-division multiplexing and mode-division multiplexing for a total of 40 channels. This link utilizes a 400 GHz frequency comb source based on a chip-scale photonic crystal resonator. Silicon-on-insulator photonic inverse-designed 4 × 4 mode-division multiplexer structures enabled a fourfold increase in data capacity. They showed less than −10 dBm of optical receiver power for error-free data transmission in 34 out of a total of 40 channels using a PRBS31 pattern…read more. TECHNICAL ARTICLE
Researchers Just Set a New Record For Data Transmission Speed
Science Alert June 4, 2022 Researchers in Japan achieved new data transmission speed record using an optical fiber network similar to those currently used for internet infrastructure. In their experiment they used 0.125 mm diameter multi-core fiber (MCF), with WDM, total of 801 parallel wavelength channels were packed into the same line. They used four cores instead of the standard one, essentially quadrupling the routes for data to take, all while keeping the cable the same size as a standard optical fiber line. They applied various other optimization, signal boosting, and decoding technologies. The team plans to continue to improve […]
Secure communication with light particles that sidesteps the reliance on polarization
Phys.org May 25, 2022 Researchers in Germany have created a scalable star-shaped quantum-key-distribution (QKD) optical-fiber network using WDM of broadband photon pairs to establish key exchange between multiple pairs of participants. They demonstrated simultaneous bipartite key exchange between any possible combination of participants and showed that the quantum bit error rate (QBER) itself can be used to stabilize the phase in the interferometers by small temperature adjustments. The key distribution is insensitive to polarization fluctuations in the network, enabling key distribution using deployed fibers even under challenging environmental conditions. They demonstrated that the network could be extended to 34 participants […]
A metasurface-based light-to-microwave transmitter for hybrid wireless communications
Phys.org May 13, 2022 Realizing signal conversion between optical and microwave frequencies typically requires a complicated relay to perform multiple operations, which will consume additional hardware/time/energy resources. An international team of researchers (China, Singapore) has reported a light-to-microwave transmitter based on the time-varying and programmable metasurface integrated with a high-speed photoelectric detection circuit into a hybrid. Such a transmitter can convert a light intensity signal to two microwave binary frequency shift keying signals by using the dispersion characteristics of the metasurface to implement the frequency division multiplexing. In demonstration the system allowed dual-channel data transmissions in a light-to-microwave link. They […]
An innovative technology for 6G communication networks
Science Daily February 15, 2022 Terahertz waveguides are required to provide versatile signal-processing functionalities. Despite fundamental components they typically rely on complex hybridization, in turn making it extremely challenging to go beyond the most elementary functions. An international team of researchers (Canada, Italy, Germany) has proposed a universal approach, in which multiscale-structured Bragg gratings can be directly etched on metal-wires. They designed a four-wire waveguide geometry, amenable to support the low-loss and low-dispersion propagation of polarization-division multiplexed terahertz signals. By engraving on the wires judiciously designed Bragg gratings based on multiscale structures, they demonstrated that it is possible to independently […]
Researchers use solar cells to achieve fast underwater wireless communication
Science Daily February 16, 2022 The greatest problem in using solar panels for underwater wireless optical communication (UWOC) systems is the limited bandwidth of the solar panel, which was originally optimized for energy harvesting rather than communication. Researchers in China studied the fundamentals of the solar array and proposed series-connected solar arrays for high-speed underwater detection. As they increased the size of the solar array from 1×1 to 3×3, the −20-dB bandwidth increased from 4.7 MHz to 24.2 MHz. To further improve the frequency response, they applied a reverse bias on the array. With a reverse bias voltage of 90 […]
New chip hides wireless messages in plain sight
Science Daily November 23, 2021 Traditional encryption methods are challenging to scale for high-bandwidth, ultralow-latency applications. An alternative approach is to use physical-layer techniques that rely on the physics of signal propagation to incorporate security features without the need for an explicit key exchange. Ensuring security using directional, narrow-beam-like features of mm-wave/THz signals has proven to be vulnerable to passive eavesdroppers. An international team of researchers (USA – Princeton University, China) has developed a space-time modulation approach that ensures security by enforcing loss of information through selective spectral aliasing towards the direction of eavesdroppers, even though the channel can be […]
Nuclear radiation used to transmit digital data wireless
Phys.org November 10, 2021 An international team of researchers (UK, Slovenia) reports on the configuration and operation of a nuclear instrumentation set-up designed to transmit digitally encoded information using fast neutrons. They measured the spontaneous emission of fast neutrons from californium-252, a radioactive isotope produced in nuclear reactors. Modulated emissions were measured using a detector and recorded. A word, the alphabet and a random number selected blindly, were encoded serially into the modulation of the neutron field and the output decoded on a laptop which recovered the encoded information on screen. A double-blind test was performed in which a number […]