The Government Circuit: Trump’s Trade War Disrupts the Electronics Ecosystem
Defense Speak Interpreted: Update on the Continuing Resolution and Budget Process for Defense
American Made Advocacy: Reshoring—About Trust, Not Just Geography
Highly Efficient, High-Speed Technology for Satellite Communications
January 8, 2016 | University of TokyoEstimated reading time: 2 minutes
A group including University of Tokyo researchers used 64 APSK, a highly efficient signal modulation technology, to successfully demonstrate 505 megabits per second (Mbps) communications with the Hodoyoshi-4 nanosatellite, the highest communication speed yet achieved with an earth-observation micro satellite. This high-speed communications technology will be of great value to future generations of earth observation micro satellites of under 100 kg.
Amplitude and phase constellation of the 64 APSK signal from the Hodoyoshi #4 micro satellite. Image of data transmitted from the Hodoyoshi #4 satellite orbiting some 600 km above the Earth to the earth station at ISAS Sagamihara. Amplitude (radius) and phase (azimuthal angle) are plotted in this color-coded map. Color codes show the frequency of occurrence of events, with red indicating more frequent occurrence. The transmitted data can be decoded from this view without error. Image credit: Hirobumi Saito.
In recent years Earth observation satellites are increasingly being equipped with high resolution cameras and radar able to discern objects of a few tens of centimeters in size. High-speed transmission systems are required to transmit the observational data obtained from such sensors to the surface of the Earth. However, the frequency bandwidth available for such use is limited, so in order to speed up transmission speeds, research has focused on development of technologies that make efficient use of the available frequency bandwidth.
When using electromagnetic waves to transmit digital data, information can be assigned to each combination of phase (frequency) and amplitude so that when the wave is received, the original information can be decoded by estimating the phase and amplitude that was transmitted. One promising technology that makes efficient use of frequency bandwidth and that is being pursued is 64 APSK modulation, or 64 amplitude phase modulation. In 64 APSK modulation, the 64 possible combinations of amplitude and phase allow the transmission of 6 bits of information, making it 1.5 to 2 times more efficient than conventional technologies. However, it is highly susceptible to noise and had yet to be demonstrated in Earth observation satellite.
Page 1 of 2
Share on:
Suggested Items
'Chill Out' with TopLine’s President Martin Hart to Discuss Cold Electronics at SPWG 2025
05/02/2025 | TopLineBraided Solder Columns can withstand the rigors of deep space cold and cryogenic environments, and represent a robust new solution to challenges facing next generation large packages in electronics assembly.
Kitron: Q1 2025 - Strong Start to the Year
04/25/2025 | KitronKitron reported first-quarter results characterised by continued momentum in the Defence & Aerospace market sector and a growing order backlog.
RTX's Collins Aerospace Enhances Capabilities to Speed Marine Corps Decision-making in Battle
04/22/2025 | RTXCollins Aerospace, an RTX business, successfully demonstrated new technology that helps the military gather and use information from a wider range of sources at Project Convergence Capstone 5, a large-scale military exercise.
AdvancedPCB Appoints Gary Stoffer as Chief Commercial Officer
04/18/2025 | PRNewswireAdvancedPCB is proud to announce the appointment of Gary Stoffer as its new Chief Commercial Officer (CCO). In this role, Stoffer will lead all sales, marketing, and commercial strategy initiatives as the company continues its mission to deliver cutting-edge PCB solutions to industries worldwide.
Real Time with... IPC APEX EXPO 2025: GreenSource's Growth and Future Developments
04/15/2025 | Real Time with...IPC APEX EXPOThings are looking bright for GreenSource. Michael Gleason shares an update on GreenSource's recent growth and upcoming changes. A recipient of a Defense Production Act Investment Program award, GreenSource is planning for new substrate capabilities. Current investments continue to enhance equipment and sustainability initiatives such as water quality. And their unique collaboration with the University of New Hampshire continues to aid their workforce development, despite recruitment challenges.