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OMG’s Space Telecommunications Interface (STI)
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OMG’s Space Telecommunication Interface (STI) Submission Discussion
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Frequency comb generation in WGM microsphere based generators for telecommunication applications
We review the frequency comb generation process, main microresonator parameters such as free spectral range (FSR) and Q-factor, previously used optical frequency comb (OFC) generator parameters and resulting frequency combs, as well as the implementation of OFC for optical data transmission. An optical frequency comb is produced in a setup based on a tapered fibre and a SiO{sub 2} microsphere. The generated frequency comb has a frequency spacing of 2 nm or 257 GHz. During the fabrication of a tapered fibre from SMF28, use is made of the transmission signal to control the taper pulling process. The final measured tapered fibre transmission is ∼96%. A microsphere whispering gallery-mode resonator (WGMR), exhibiting a Q-factor of at least 2 × 10{sup 7}, is fabricated from an optical fibre with a thicker core than SSMF. Moreover, for future experiments, a frequency comb generator based on a free-space setup consisting of lenses, a prism, and a microsphere is developed, and the Q-factor dependence on different distances between the prism and the microsphere is investigated. (optical components of fibre-optic communication lines)
Extended spin relaxation times of optically addressed vanadium defects in silicon carbide at telecommunication frequencies
Optically interfaced solid-state defects are promising candidates for quantum communication technologies. The ideal defect system would feature bright telecom emission, long-lived spin states, and a scalable material platform, simultaneously. Here, in this study, we use one such system, vanadium (V 4+ ) in silicon carbide, to establish a potential telecom spin-photon interface within a mature semiconductor host. This demonstration of efficient optical spin polarization and readout facilitates all-optical measurements of temperature-dependent spin relaxation times (T 1 ). By using this technique, and lowering the temperature from approximately 2 K to approximately 100 mK, we observe a remarkable 4-orders-of-magnitude increase in spin T 1 across all measured sites, with site-specific values ranging from 57.1 ms to 27.9 s. Furthermore, we identify the underlying relaxation mechanisms, which involve a two-phonon Orbach process, indicating the opportunity for strain tuning to enable qubit operation at higher temperatures. These results position V 4+ in SiC as a prime candidate for scalable quantum nodes in future quantum networks.
NM Science, Technology and Telecommunications committee: State of the Lab [Slides]
Our priority throughout COVID has been protecting our employees and our communities. To this end, we stood up internal testing and vaccination programs; kept disease risk low via maximum teleworking; leveraged world-class expertise to support federal and state through disease modeling and forecasting; and stored vaccines for the school district. COVID-19 taught us there are many ways to leverage technology to work safely and effectively.
Some economic problems of international space telecommunications, volume II
Recapitulation of processes and data sources used in deriving intelsat system requirements through 1975
Radio sciences and interplanetary spacecraft telecommunications.
Radio propagation considered for solar system exploration, discussing spacecraft role
An analysis of the telecommunication performance of a data-relay satellite system.
Data relay satellite system to provide communication capability between earth orbiting space vehicles and Mission Control Center
State of the technique on surge protection of telecommunication installations with surge diverters
Surge protection in communication systems by diverters
Telecommunications Division
Coding models, antenna designs, and optimization of spacecraft communications systems
Power requirements for deep-space telecommunication links.
Power requirements for tracking, telecommand and telemetry of spacecraft over interplanetary distances, considering transmission problems, equipment weight and reliability
Mariner /Venus 1962/ flight telecommunication system
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Spacecraft telecommunications systems - A digital command system development
All digital, single channel command subsystem for spacecraft communication
Program on application of communications satellites to educational development. Computer-based instruction: A background paper on its status, cost/effectiveness and telecommunications requirements
Status, cost/effectiveness, and telecommunication/satellite requirements of computer-based instruction
An efficient and versatile telemetry subcarrier demodulation technique for deep space telecommunications
Wideband subcarrier frequencies demodulation technique for uncoded or coded PSK telemetry over large input SNR range for deep space interplanetary communication
Interplex: An analysis of optimized power allocations for two and three channel PSK/PM telecommunications systems
Optimal design concepts are presented for two- and three-channel telemetry modes in the context of the Mariner Venus-Mercury 1973 mission and the usefulness of interplex modulation techniques is discussed. These ideas are applied as an example to one Mariner Venus-Mercury 1973 telemetry mode to demonstrate that interplex can reduce the required total average power by more than 2 dB in some cases.
Tracking and data relay satellite system configuration and tradeoff study. Volume 2: Part 2 telecommunications design
For abstract, see .