MIT News September 6, 2022 Researchers at MIT Lincoln Laboratory have installed a Multi-Band Test Terminal (MBTT) which can rotate 15 degrees per second, completing a single revolution in 24 seconds. At this speed, the MBTT can detect and track satellites in medium and low Earth orbit. The MBTT is designed to be easily reconfigured to support multiple radio frequency (RF) bands used for military and commercial satellite SATCOM systems. Since its installation, it has supported a wide range of tests and experiments involving protected tactical waveform (PTW). It is also supporting international outreach efforts led by Space Systems Command […]
Tag Archives: Satellite communication
Researchers complete high-precision time-frequency dissemination
Phys.org April 26, 2021 Microwave-based satellite–ground links cannot fully satisfy the requirements of metrology, navigation, positioning, and very long baseline interferometers. Researchers in China investigated the possibility of an optical-based satellite–ground link, where the transferred carriers are pulsed lasers, resulting in a link with a high time resolution and a large ambiguous range. They analyzed the parameters of satellites in different orbits and concluded that high-orbit links enable more stable time–frequency comparison or dissemination by taking advantage of the long duration, a large common view range, and the lower relativistic effects. They performed a 16 km free-space transfer experiment to […]
New laser to help clear the sky of space debris
Phys.org April 12, 2021 The laser beams used for tracking space junk use infrared light and are not visible. The new guide star laser, which is mounted on a telescope, developed by an international team of researchers (from Australia, Japan, USA) propagates a visible orange beam into the night sky to create an artificial star that can be used to accurately measure light distortion between Earth and space. This guiding orange light enables adaptive optics to sharpen images of space debris. It can also guide a second, more powerful infra-red laser beam through the atmosphere to precisely track space debris or […]
Greater connectedness in remote areas: A Ka-band transceiver for satellite communications
EurekAlert August 4, 2020 The transceiver developed by researchers in Japan using standard CMOS technology uses 27-31 GHz frequency range for uplink and 17-21 GHz range for downlink. A high-quality transformer is used to achieve efficient power use and high linearity in transmission, resulting in lower distortion during transmission. Two RX channels allows for receiving signals from two satellites simultaneously in parallel using either two independent polarization modes or two different frequencies. It can perform adjacent-channel interference cancellation increasing the dynamic range of the system, thus allowing it to operate correctly even in less-than-ideal scenarios with stronger noise and interference. […]
New Antenna Will Boost UAV Communication with Satellites
IEEE Spectrum March 10, 2020 Conventional sabre-like antennas generate a donut-shape radiation pattern, which provides an omnidirectional coverage and is ideal for air-to-ground communication. However, a donut-shape pattern has a null at its zenith which inhibits communication with other satellites. To provide signal directly above the antenna researchers in China designed a novel sabre-like antenna incorporated two metal radiators into the design. The first is a monopole, which is perpendicular to the ground with an omnidirectional pattern. The second is a dipole, which is parallel to the ground with broadside pattern – creating a signal that fills the blind spot […]