scholarly journals Нейросетевой имитатор нестационарной среды в адаптивной системе передачи данных

Author(s):  
А.А. Невзоров ◽  
А.А. Орлов ◽  
Д.А. Станкевич

Article is devoted to new method for optimizing the data transmission channel, based on neural network simulator of a nonstationary physical medium. The proposed method allows reducing the probability of reception error to corresponding level of binary phase shift keying with a small signal-to-noise ratio.

2012 ◽  
Vol 22 (03) ◽  
pp. 1250009 ◽  
Author(s):  
M. A. LOPEZ-GORDO ◽  
F. PELAYO ◽  
A. PRIETO ◽  
E. FERNANDEZ

Fully auditory Brain-computer interfaces based on the dichotic listening task (DL-BCIs) are suited for users unable to do any muscular movement, which includes gazing, exploration or coordination of their eyes looking for inputs in form of feedback, stimulation or visual support. However, one of their disadvantages, in contrast with the visual BCIs, is their lower performance that makes them not adequate in applications that require a high accuracy. To overcome this disadvantage, we employed a Bayesian approach in which the DL-BCI was modeled as a Binary phase shift keying receiver for which the accuracy can be estimated a priori as a function of the signal-to-noise ratio. The results showed the measured accuracy to match the predefined target accuracy, thus validating this model that made possible to estimate in advance the classification accuracy on a trial-by-trial basis. This constitutes a novel methodology in the design of fully auditory DL-BCIs that let us first, define the target accuracy for a specific application and second, classify when the signal-to-noise ratio guarantees that target accuracy.


2011 ◽  
Vol 20 (08) ◽  
pp. 1637-1658 ◽  
Author(s):  
CHIA-CHUN TSAI ◽  
SHENG-BIN DAI ◽  
TRONG-YEN LEE

In this paper, we design and implement an integrated circuit system for contactless interface transmission to conform the transfer protocol of ISO/IEC 14443-2 Type B. The system consists of two major parts, interrogator and transponder, for magnetic power and data transmission. The power and data can synchronously be transferred from the interrogator to the transponder with 10% amplitude shift keying modulation of mixing both carrier 13.56 MHz and data rate 106 Kbps. Another data can be backward to the interrogator from the transponder with the mixed binary phase shift keying modulation. Simulation results to the whole chip based on TSMC 0.35 μm CMOS process have approved using HSPICE.


2012 ◽  
Vol 239-240 ◽  
pp. 994-999
Author(s):  
Guang Zu Liu ◽  
Jian Xin Wang

To improve the estimation accuracy of non-data-aided (NDA) signal-to-noise ratio (SNR) estimators at low SNR value, A novel estimation technique for binary phase-shift keying and quadrature phase-shift keying signals in complex additive white Gaussian noise channel is proposed. The mathematical relation between SNR and the ratio of two simple statistical computations is derived, then SNR is determined by looking up a table. Its accuracy surpasses other NDA estimators, approaching closely to the Cramer-Rao lower bound at SNR > 5dB.


Author(s):  
Maksim S. Grebenev ◽  
Alexander V. Kondrashov ◽  
Vadim V. Perepelovsky

In this paper, the method of binary data transmission and receiving is first suggested and experimentally investigated. The method uses dynamical chaos as a source of multiple carrier frequencies. On the server side, the transmitter configures informational signal in the form of frequency grid with chaotically varying frequencies of the spectrum with their amplitudes corresponding to transmitted information message. On the client side, the transmitted information is re-stored using chaotically selected spectral windows. Synchronization of the server and client dynamic chaos generators is achieved by means of TCP/IP protocol. Suggested method is based on combined transmission of information message via transmission channel and background signal. Power of background signal significantly exceeds power of informational one. The method allows using different informational signal as a background signal, such as voice message. The addition of low power chaotically formed frequency grid signal does not lead to significant background signal formation either in spectral or in time domain. Thus, the described method allows repeated application of the transmission channel. The effect of signal-to noise ratio of the order of the filter implementing the spectral windows in the receiver and the width of the spectral window is investigated. Signal-to-noise ratio can be reduced with increasing filter order and spectral window width.


Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4347
Author(s):  
Boyun Lyu ◽  
Yu Hua ◽  
Jiangbin Yuan ◽  
Shifeng Li

The Enhanced Loran (eLoran) system is valued for its important role in the positioning, navigation, and timing fields; however, with its current modulation methods, low data rate restricts its development. Ultra narrow band (UNB) modulation is a modulation method with extremely high spectrum utilization. If UNB modulation can be applied to the eLoran system, it will be very helpful. The extended binary phase shift keying modulation in UNB modulation is selected for a detailed study, parameters and application model are designed according to its unique characteristics of signal time and frequency domains, and it is verified through simulation that the application of this modulation not only meets the design constraints of the eLoran system but also does not affect the reception of the respective signals of both parties. Several feasible schemes are compared, analyzed, and selected. Studies have revealed that application of UNB modulation in the eLoran system is feasible, and it will increase the data rate of the system by dozens of times.


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