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We develop two resistant to noise secure communication schemes based on time-delayed feedback oscillators with switching of chaotic regimes. One of the proposed schemes exploits the identical synchronization between the transmitter and receiver while another system uses the regime of generalized synchronization. The proposed schemes are studied numerically and implemented in a physical experiment.
We have studied the emission properties of combined intrinsic Josephson junction (IJJ) stacks. The IJJ THz oscillators were fabricated by two different methods : standard Ar ion milling and hydrochloric acid modification processes. We observed that the series connection of two stacks improves the heating problem. For the stacks with a large number of IJJs, intense emissions were observed only in the...
This work presents a distributed detection system based on coupled oscillator arrays (COAs). The distributed detection is based on the synchronization phenomena. When the sensor elements detect an event they set the frequency of the oscillators to one value f1. If the sensors do not detect any event then the oscillators are set to f0. Due to the synchronization properties all the oscillator elements...
One of the most challenging phenomena that can be observed in an ensemble of interacting agents is that of self-organisation, viz. emergent, collective behaviour, also known as synergy. The concept of synergy is well-known in the artificial intelligence community, in social science, and in management and economic sciences. The paradigm may be expressed by identifying an ensemble performance measure...
In this paper, we describe an architecture of a distributed ADPLL (All Digital Phase Lock Loop) network based on bang-bang phase detectors that are interconnected asymmetrically. It allows an automatic selection between two operating modes (uni- and bidirectional) to avoid mode-locking phenomenon, to accelerate the network convergence and to improve the robustness to possible network failures in comparison...
This paper tries to answer an interesting question: Is there any synchronized oscillation in network-wide urban traffic flow? Particularly, we apply the spectral envelope method to extract the common oscillation frequencies of a set of traffic flow time series collected from several detectors distributed on a two dimensional (2D) urban traffic network. Results show that several local synchronized...
To have higher resolution of distance in the laser scanner using the phase demodulation method, to demodulate using an intermediate frequency is advantageous. This method is called the multiple phase demodulation method. In the multiple phase demodulation method several frequencies are used for signal processing. These signals are made from the oscillator and the programmable clock source. Even though...
Presented paper is devoted to theoretical modeling and experimental investigation of transferring of initial phase of low frequency oscillations with modulation of carrier oscillations in separate high frequency link from one part of testing link to another. The main goal of this investigation is the determination of influence of phase stability and amplitude one of separate high frequency link on...
This paper proposes a new three-phase positive sequence detector. The scheme is based on a stationary reference frame and a Moving Average Filter (MAF) that guarantees the complete cancellation of harmonics and grid imbalances. The performance of the MAF is mathematically analyzed and a proper selection of the optimal filter's window width is realized. The proposed detector operates in open loop and...
For portable deep space communications applications where low power is a key requirement At the receiver, non coherent FSK quadrature detectors is suitable that enable to develop novel design and digitally implemented as VLSI circuits An important consideration in an FSK low power receiver is whether to use coherent detection or non coherent detection. This question arises because the carrier phase,...
This paper proposes a three-phase positive sequence detector that does not require any parameter to be adjusted. It operates in open loop and there is not any PI controller that needs to be tuned. The scheme includes the use of the Park transformation and moving average filters. Performance of the moving average filter is mathematically analyzed and represented in a Bode diagram. The analysis allows...
In this paper the Duffing oscillator is applied to solve high transmitter power consumption and high probability of intercept of underwater mine. A chaotic oscillator has the property of being sensitive to weak signal and being immune to noise, which leads to a potential application in weak signal detection. The weak signals can be used as the outside periodic exciter and be brought in the Duffing...
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