scholarly journals Adaptation of the CMS Radio Link According to the Information Rate in the Presence of Interference

2020 ◽  
Vol 7 (4) ◽  
pp. 51-55
Author(s):  
A. V. Kruglov ◽  
◽  
O. I. Khomov ◽  
Keyword(s):  
Information Transfer ◽  
Cross Correlation ◽  
Radio Link ◽  
Information Channel ◽  
Transfer Rates ◽  
Measurement Systems ◽  
Adaptive Receiver ◽  
Urgent Task ◽  
Processing Algorithms ◽  
Information Channels

In modern command and measurement systems (CMS), phase-shift keyed signals are widespread, which, with relatively simple methods of formation, have a low level of side lobes of the autocorrelation function (ACF). Also, in recent years, a number of studies have been carried out on the implementation of the principle of constructing the CMS, based on the adaptation of processing algorithms to the properties of useful signals and interference. On the basis of this principle, an algorithm for adapting the CMS radio link has been developed, which makes it possible to analyze information channels at various speeds and automatically connect the selected channel, which is an urgent task for controlling low-orbit spacecraft. The article proposes a receiver scheme with parallel reception of several information channels with different information transfer rates. The analysis of autocorrelation and cross-correlation functions made it possible to conclude that the data obtained do not contradict the assumptions about the possibility of implementing an adaptive receiver with the choice of an information channel in terms of speed. It is shown that the use of such a receiving device with an algorithm for selecting and switching information channels according to the reception rate provides a significant gain in information transmission time in comparison with traditional reception and switching of speeds by commands in conditions of complex interference stop.

scholarly journals Creation of a Hardware-Software Dynamic Signal Simulator of the Upgraded Inter-Satellite Radio Link of the GLONASS System

2021 ◽  
Vol 8 (3) ◽  
pp. 63-71
Author(s):  
A. A. Cherkasova ◽  
◽  
R. F. Salakhov ◽  
D. A. Astaсhov ◽  
◽  
...  
Keyword(s):  
Information Transfer ◽  
Doppler Frequency ◽  
Radio Link ◽  
Satellite Measurements ◽  
Process Measurement ◽  
Signal Simulator ◽  
Information Transfer Rate ◽  
The Difference ◽  
Measuring Signal ◽  
Orthogonal Phase

This work is aimed at creating a hardware-software signal simulator of the upgraded inter-satellite radio link (ISRL) of the GLONASS system. The simulator shapes ISRL signals with dynamically changing parameters of the Doppler frequency shift and delay, which correspond to the mutual dynamics of spacecraft (SC) motion of the GLONASS system. The upgraded inter-satellite radio link will provide (as compared to the current ISRL) an increase in the information transfer rate of up to four times, as well as boost the accuracy of measuring the distance between satellites by two times. Modernization consists in complementing the radio signal of the second orthogonal (phase-shifted carrier frequency by 90 degrees relative to the existing one) component. To modernize the ISRL, it is necessary to create and verify new equipment for receiving and transmitting signals of the upgraded ISRL of the GLONASS system. The simulator is designed to process measurement algorithms embedded in the on-board equipment for inter-satellite measurements and assess their consistency. Consistency evaluation consists in measuring and analyzing the difference between the Doppler parameters and delay introduced into the signal and the estimation of these parameters in the receiving equipment of the ISRL. This difference will be the measurement error. Dynamic simulation is performed for 24 system points, corresponding to GLONASS satellites, on the half-period of satellite revolution (20 280 seconds). The signal is generated at the input of the antenna-feeder device of one of the satellites in accordance with the information for generating the measuring signal, parameters of the transmitters of the signals of the upgraded ISRL and the almanac of the satellite constellation (because the signal at the input of the antenna-feeder device of the navigation receiver incomes from several SC) specified by the user.

Modeling of Quantum Key Distribution System for Secure Information Transfer

2014 ◽  
pp. 811-840
Author(s):  
K. E. Rumyantsev ◽  
D. M. Golubchikov
Keyword(s):  
Distribution System ◽  
Quantum Key Distribution ◽  
Information Transfer ◽  
Distribution Systems ◽  
Key Distribution ◽  
Photon State ◽  
Secure Information ◽  
Sequence Production ◽  
Security Infrastructure ◽  
Processing Algorithms

This chapter is an analysis of commercial quantum key distribution systems. Upon analysis, the generalized structure of QKDS with phase coding of a photon state is presented. The structure includes modules that immediately participate in the task of distribution and processing of quantum states. Phases of key sequence productions are studied. Expressions that allow the estimation of physical characteristics of optoelectronic components, as well as information processing algorithms impact to rate of key sequence production, are formed. Information security infrastructure can be utilized, for instance, to formulate requirements to maximize tolerable error level in quantum channel with a given rate of key sequence production.

scholarly journals A Hybrid Speller Design Using Eye Tracking and SSVEP Brain–Computer Interface

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 891 ◽  
Author(s):  
Malik M. Naeem Mannan ◽  
M. Ahmad Kamran ◽  
Shinil Kang ◽  
Hak Soo Choi ◽  
Myung Yung Jeong
Keyword(s):  
Eye Tracking ◽  
Classification Accuracy ◽  
Information Transfer ◽  
High Speed ◽  
Communication Channel ◽  
Computer Interface ◽  
Stimuli Responsive ◽  
Transfer Rates ◽  
Computer Interfaces ◽  
Large Numbers

Steady-state visual evoked potentials (SSVEPs) have been extensively utilized to develop brain–computer interfaces (BCIs) due to the advantages of robustness, large number of commands, high classification accuracies, and information transfer rates (ITRs). However, the use of several simultaneous flickering stimuli often causes high levels of user discomfort, tiredness, annoyingness, and fatigue. Here we propose to design a stimuli-responsive hybrid speller by using electroencephalography (EEG) and video-based eye-tracking to increase user comfortability levels when presented with large numbers of simultaneously flickering stimuli. Interestingly, a canonical correlation analysis (CCA)-based framework was useful to identify target frequency with a 1 s duration of flickering signal. Our proposed BCI-speller uses only six frequencies to classify forty-eight targets, thus achieve greatly increased ITR, whereas basic SSVEP BCI-spellers use an equal number of frequencies to the number of targets. Using this speller, we obtained an average classification accuracy of 90.35 ± 3.597% with an average ITR of 184.06 ± 12.761 bits per minute in a cued-spelling task and an ITR of 190.73 ± 17.849 bits per minute in a free-spelling task. Consequently, our proposed speller is superior to the other spellers in terms of targets classified, classification accuracy, and ITR, while producing less fatigue, annoyingness, tiredness and discomfort. Together, our proposed hybrid eye tracking and SSVEP BCI-based system will ultimately enable a truly high-speed communication channel.

Optimizing information‐transfer rates for human communication

2006 ◽  
Vol 119 (5) ◽  
pp. 3237-3237
Author(s):  
Charlotte M. Reed ◽  
Nathaniel I. Durlach ◽  
Hong Z. Tan
Keyword(s):  
Information Transfer ◽  
Human Communication ◽  
Transfer Rates

scholarly journals Brain–Computer Interface Spellers for Communication: Why We Need to Address Their Security and Authenticity

2020 ◽  
Vol 10 (3) ◽  
pp. 139
Author(s):  
Anirban Dutta
Keyword(s):  
Research And Development ◽  
Information Transfer ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Brain Computer Interfaces ◽  
Transfer Rates ◽  
Computer Interfaces ◽  
Significant Research

Brain–Computer Interfaces (BCI) have witnessed significant research and development in the last 20 years where the main aim was to improve their accuracy and increase their information transfer rates (ITRs), while still making them portable and easy to use by a broad range of users [...]

scholarly journals INFORMATION TRANSFER RATES IN SPIN QUANTUM CHANNELS

2007 ◽  
Vol 05 (04) ◽  
pp. 439-455 ◽  
Author(s):  
DAVIDE ROSSINI ◽  
VITTORIO GIOVANNETTI ◽  
ROSARIO FAZIO
Keyword(s):  
Quantum Information ◽  
Information Transfer ◽  
Transmission Efficiency ◽  
Spin Chains ◽  
Quantum Channels ◽  
Transfer Rates ◽  
Temporal Correlations ◽  
Spin Quantum ◽  
Communication Efficiency

We analyze the communication efficiency of quantum information transfer along unmodulated spin chains by computing the communication rates of various protocols. The effects of temporal correlations are discussed, showing that they can be exploited to boost the transmission efficiency.

scholarly journals High-speed spelling with a noninvasive brain–computer interface

2015 ◽  
Vol 112 (44) ◽  
pp. E6058-E6067 ◽  
Author(s):  
Xiaogang Chen ◽  
Yijun Wang ◽  
Masaki Nakanishi ◽  
Xiaorong Gao ◽  
Tzyy-Ping Jung ◽  
...  
Keyword(s):  
Information Transfer ◽  
High Speed ◽  
Target Identification ◽  
Modulation Method ◽  
Identification Algorithm ◽  
Calibration Data ◽  
Transfer Rates ◽  
Modulation And Demodulation ◽  
Individual Calibration ◽  
High Consistency

The past 20 years have witnessed unprecedented progress in brain–computer interfaces (BCIs). However, low communication rates remain key obstacles to BCI-based communication in humans. This study presents an electroencephalogram-based BCI speller that can achieve information transfer rates (ITRs) up to 5.32 bits per second, the highest ITRs reported in BCI spellers using either noninvasive or invasive methods. Based on extremely high consistency of frequency and phase observed between visual flickering signals and the elicited single-trial steady-state visual evoked potentials, this study developed a synchronous modulation and demodulation paradigm to implement the speller. Specifically, this study proposed a new joint frequency-phase modulation method to tag 40 characters with 0.5-s-long flickering signals and developed a user-specific target identification algorithm using individual calibration data. The speller achieved high ITRs in online spelling tasks. This study demonstrates that BCIs can provide a truly naturalistic high-speed communication channel using noninvasively recorded brain activities.

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