Orbit trim propulsion requirements for sun synchronous satellites
Orbit trim propulsion requirements for sun synchronous satellites
SUN↗
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Results for “Synchronization”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Optimal control applications for electrothermal multijet systems on synchronous earth spacecraft
Optimal control applications for electrothermal multijet systems for attitude control and station keeping of 24-hour synchronous satellite
ATTITUDE CONTROL↗
Evaluation of an ion propulsion system for a synchronous spacecraft mission
Ion propulsion system evaluation for attitude control and stationkeeping of synchronous satellites
ATTITUDE CONTROL↗
Servo control and data synchronization study
Breadboard magnetic tape recorder-reproducer with servocontrol and data synchronization
MAGNETIC TAPE RECORDER↗
Orbital regression of synchronous satellites due to the combined gravitational effects of the sun, the moon and the oblate earth
Orbital regression of synchronous satellites due to combined gravitational effects of sun, moon, and oblate earth
GRAVITATIONAL EFFECT↗
The automatic antenna position control system for the ATS synchronous orbit spin-stabilized satellite.
Automatic directional-antenna position control system for ATS synchronous orbit spin- stabilized satellite
SYNCHRONOUS SATELLITE↗
Synchronous satellite station-keeping.
Synchronous orbit stationkeeping techniques, examining thrust control requirements of spin- stabilized spacecraft
THRUST CONTROL↗
Evaluation of an ion propulsion system for a synchronous spacecraft mission.
Thrust, power and performance requirements for synchronous satellite simulated for evaluating ion propulsion feasibility
SPACECRAFT PROPULSION↗
Optimal control applications for electrothermal multijet systems on synchronous earth spacecraft.
Multijet electrothermal systems for attitude control and stationkeeping of synchronous communications satellite
STATIONKEEPING↗
Precious bits: frame synchronization in Jet Propulsion Laboratory's Advanced Multi-Mission Operations System (AMMOS)
The Jet Propulsion Laboratory's (JPL) Advanced Multi-Mission Operations System (AMMOS) system processes data received from deep-space spacecraft, where error rates are high, bit rates are low, and every bit is precious. Frame synchronization and data extraction as performed by AMMOS enhanced data acquisition and reliability for maximum data return and validity.
code↗
Quantum Atomic Clock Synchronization: An Entangled Concept of Nonlocal Simultaneity
We demonstrate that two spatially separated parties (Alice and Bob) can utilize shared prior quantum entanglement, as well as a classical information channel, to establish a synchronized pair of atomic clocks.
quantum information processing atomic clocks quant↗
Suppressed Carrier Synchronizers for ISI Channels
We demonstrate a class of suppressed carrier synchronization loops that are motivated by MAP estimation theory and in the presence of ISI outperform the conventional I-Q loop which is designed on the basis of zero ISI (wideband assumption). The measure of comparison used is the so-called.
synchronization loops↗
Acquisition Performance Comparison of the Generalized Maxium A Posteriori Symbol Synchronizer Versus the Data-Transition Tracking Loop
A generalized maxium a posteriori (MAP), symbol synchronizer for arbitrary nonoverlapping pulse shape and data-transition density is derived, and a simplified realization is presented.
Maxium A Posteriori (MAP) signal-to-noise ratio (S↗
Information-reduced Carrier Synchronization of Iterative Decoded BPSK and QPSK using Soft Decision (Extrinsic) Feedback
This paper addresses the carrier-phase estimation problem under low SNR conditions as are typical of turbo- and LDPC-coded applications. In previous publications by the first author, closed-loop carrier synchronization schemes for error-correction coded BPSK and QPSK modulation were proposed that were based on feeding back hard data decisions at the input of the loop, the purpose being to remove the modulation prior to attempting to track the carrier phase as opposed to the more conventional decision-feedback schemes that incorporate such feedback inside the loop. In this paper, we consider an alternative approach wherein the extrinsic soft information from the iterative decoder of turbo or LDPC codes is instead used as the feedback.
carrier synchronization↗
Frame Synchronization Without Attached Sync Markers
A new frame synchronizer was presented. It eliminates the need to transmit attached sync markers (ASMs). In approximately 10 iterations, the decoder can distinguish between sync and non-sync states.
Attached Sync Markers (ASMs)↗
Turbo-code performance with imperfect carrier synchronization
The threshold performance of deep-space telemetry is characterized for four turbo codes. The mathematical models given here are based on simulations that account for imperfect carrier synchronization.
turbo↗
Closed Loop Carrier Phase Synchronization Techniques Motivated by Likelihood Functions
This paper reexamines the notion of closed loop carrier phase synchronization motivated by the theory of maximum a posterior (MAP) phase estimation with emphasis on the development of new structures based on both maximum likelihood (ML) and average-likelihood (AL) functions.
Closed↗
Synchronized Formation Rotation and Attitude Control of Multiple Free-flying Spacecraft
In the observation slewing of long base-line interferometers formed by multiple free-flying spacecraft in formation, it is required to rotate the entire formation about a given axis, and to synchronize individual spacecraft rotation with formation rotation.
long↗