Performance comparison of two synchronization schemes for Colpitts circuits based chaotic communication system over noise channel
15 Jun 2004-Vol. 2, pp 1276-1279
TL;DR: The mathematical derivation and numeric simulations indicate that the error feedback synchronization scheme outperforms the Pecora-Carroll synchronization scheme when the chaotic signal is transmitted over a noisy channel in which there exist an additive white Gaussian noise source and a channel filter.
Abstract: The synchronization performance of the Pecora-Carroll scheme and the error feedback scheme was investigated for two coupled chaotic Colpitts circuits. Both the mathematical derivation and numeric simulations indicate that the error feedback synchronization scheme outperforms the Pecora-Carroll synchronization scheme when the chaotic signal is transmitted over a noisy channel in which there exist an additive white Gaussian noise source and a channel filter. As a result, the information embedded in the chaotic signal, which passes a noisy channel from the transmitter to the receiver, can be recovered in a better way when the error feedback synchronization scheme is used.
Citations
More filters
TL;DR: System simulations show that such RADAR can still work in an environment when the signal-to-noise ratio (SNR) is lower than −20 dB and the “multi-user” property is realized.
Abstract: In this paper, we present a new scheme for the realization of a wide-band chaotic RADAR system. The remarkable characteristics of such scheme are: (1) Wide-band chaotic signal generated from microwave chaotic Colpitts oscillator is directly used as the RADAR signal; (2) Chaos synchronization is used to recover the chaotic signal from the back-scattered signal by targets; (3) The intrinsic sensitivities of the chaotic signal to the parameters of the chaotic circuit and to the initial conditions are used to realize the “multi-user” property. System simulations show that such RADAR can still work in an environment when the signal-to-noise ratio (SNR) is lower than −20 dB. † Also with Zhejiang University City College, Hangzhou, 310025, China.
58 citations
Cites background from "Performance comparison of two synch..."
...[25], where both the mathematical derivation and numeric simulations indicate that the error feedback synchronization scheme outperforms the former one when the chaotic signal is transmitted over a noisy channel with an additive white Gaussian noise and a channel filter....
[...]
TL;DR: This work solves the problem of master-slave synchronization of fourth-order Lu's hyperchaotic systems via feedback control via Lyapunov's second stability method by using only one control input that enters in the slave system.
Abstract: We solve the problem of master-slave synchronization of fourth-order Lu's hyperchaotic systems via feedback control. We use only one control input that enters in the slave system. We show that this simple feedback suffices to synchronize both systems exponentially fast. We provide a proof of stability and convergence (hence, that synchronization takes place) via Lyapunov's second stability method. We provide some numeric simulations that illustrate our findings.
30 citations
Cites background from "Performance comparison of two synch..."
...On the other hand, a number of chaotic systems continue to appear in the literature: beyond the celebrated Lorenz and Rössler systems, we shall mention the Chen system [23], the Colpitts circuit [21], and different versions of the so-called Lü and Chen system [15], [17]....
[...]
TL;DR: In this article, the synchronization of chaotic Colpitts circuits using a particle filter (PF) to combat the additive white Gaussian noise (AWGN) channel effect is studied by numeric simulations.
Abstract: In this paper, synchronization of chaotic Colpitts circuits using a particle filter (PF) to combat the additive white Gaussian noise (AWGN) channel effect is studied by numeric simulations. A novel PF algorithm suitable for chaos synchronization is proposed. With this algorithm, chaos synchronization of Colpitts circuits can be achieved and maintained in AWGN channels. Parameters in the proposed PF algorithm are studied to understand their effects on synchronization performance. The synchronization performance using the proposed PF algorithm is compared with those using other digital filters, such as the extended Kalman filter and the generic PF. It is found that the proposed PF algorithm performs better than the other digital filters. Simulation results also show that the particle number is not very critical to the synchronization performance when this PF algorithm is used.
16 citations
Additional excerpts
...Under ideal synchronization conditions, mathematical analysis and simulation results have confirmed that perfect synchronization can be achieved when no parameter mismatches and channel distortions are considered [10, 14, 15, 17 , 19]....
[...]
TL;DR: System simulations show that such RADAR can still work in an environment when the signal-to-noise ratio (SNR) is −20 dB, and the scheme is suitable for wide-band noisesignal RADAR.
Abstract: In this paper, we present a new scheme for the realization of a wide-band noisesignal RADAR utilizing wide-band chaotic signal generated from microwave chaotic Colpitts oscillator. System simulations show that such RADAR can still work in an environment when the signal-to-noise ratio (SNR) is −20 dB.
9 citations
TL;DR: In this paper, the synchronization of chaotic Colpitts circuits, using adaptive controllers to combat circuit parameter mismatches and channel distortions, is studied by numerical simulations. But no obvious enhancements regarding the effect on AWGN channel were shown.
Abstract: In this work, synchronization of chaotic Colpitts circuits, using adaptive controllers to combat circuit parameter mismatches and channel distortions, is studied by numerical simulations. Synchronization errors caused by different main circuit components are compared, and compensation for time-constant and time-varying circuit parameter mismatches is demonstrated. Different kinds of channel distortions, including time-constant and time-varying channel attenuation, Additive White Gaussian Noise (AWGN) are all investigated by numerical simulations and discussed. Simulation results indicated that the synchronization performance of chaotic Colpitts circuits can be greatly improved by applying adaptive controllers when parameter mismatches and channel attenuation are considered as time-constant or time-varying, but have no obvious enhancements regarding the effect on AWGN channel.
9 citations
Cites background or methods from "Performance comparison of two synch..."
...Also, we studied the synchronization performance under two main channel distortions, namely channel fading and Additive White Gaussian Noise (AWGN), and employed adaptive controllers to combat such distortions....
[...]
...In this section, two major channel distortions, channel fading and Additive White Gaussian Noise (AWGN), are considered....
[...]
...In this simulation, we considered the AWGN as the only channel distortion....
[...]
...However, since the feedback scheme applied in our system is rather tolerable to the AWGN (Shi et al., 2004), the adaptive controller seems not necessary in practical communications....
[...]
...…and their capabilities for synchronizing chaotic Colpitts circuits when channel distortions and parameter mismatches were taken into account; and used error feedback synchronization scheme as Shi et al.(2004) found that it outperformed other schemes like the Pecora-Carroll synchronization scheme....
[...]
References
More filters
TL;DR: It is shown that driving with chaotic signals can be done in a robust fashion, rather insensitive to changes in system parameters, and the calculation of the stability criteria leads naturally to an estimate for the convergence of the driven system to its stable state.
Abstract: We generalize the idea of driving a stable system to the situation when the drive signal is chaotic. This leads to the concept of conditional Lyapunov exponents and also generalizes the usual criteria of the linear stability theorem. We show that driving with chaotic signals can be done in a robust fashion, rather insensitive to changes in system parameters. The calculation of the stability criteria leads naturally to an estimate for the convergence of the driven system to its stable state. We focus on a homogeneous driving situation that leads to the construction of synchronized chaotic subsystems. We apply these ideas to the Lorenz and R\"ossler systems, as well as to an electronic circuit and its numerical model.
888 citations
TL;DR: The theory of conventional telecommunications is extended to chaotic communications, chaotic modulation techniques and receiver configurations are surveyed, and chaotic synchronization schemes are described.
Abstract: For pt. I see ibid., vol. 44, p. 927-36 (1997). In a digital communications system, data are transmitted from one location to another by mapping bit sequences to symbols, and symbols to sample functions of analog waveforms. The analog waveform passes through a bandlimited (possibly time-varying) analog channel, where the signal is distorted and noise is added. In a conventional system the analog sample functions sent through the channel are weighted sums of one or more sinusoids; in a chaotic communications system the sample functions are segments of chaotic waveforms. At the receiver, the symbol may be recovered by means of coherent detection, where all possible sample functions are known, or by noncoherent detection, where one or more characteristics of the sample functions are estimated. In a coherent receiver, synchronization is the most commonly used technique for recovering the sample functions from the received waveform. These sample functions are then used as reference signals for a correlator. Synchronization-based coherent receivers have advantages over noncoherent receivers in terms of noise performance, bandwidth efficiency (in narrow-band systems) and/or data rate (in chaotic systems). These advantages are lost if synchronization cannot be maintained, for example, under poor propagation conditions. In these circumstances, communication without synchronization may be preferable. The theory of conventional telecommunications is extended to chaotic communications, chaotic modulation techniques and receiver configurations are surveyed, and chaotic synchronization schemes are described.
474 citations
TL;DR: In this article, the authors present experimental results and SPICE simulations of chaos in a Colpitts oscillator and show that the nonlinear dynamics of this oscillator may be modeled by a third-order autonomous continuous-time circuit consisting of a linear inductor, two linear capacitors, 2 linear resistors, two independent voltage sources, a linear current-controlled current source, and a single voltage-controlled nonlinear resistor.
Abstract: In this work, we present experimental results and SPICE simulations of chaos in a Colpitts oscillator. We show that the nonlinear dynamics of this oscillator may be modeled by a third-order autonomous continuous-time circuit consisting of a linear inductor, two linear capacitors, two linear resistors, two independent voltage sources, a linear current-controlled current source, and a single voltage-controlled nonlinear resistor. The nonlinear resistor has a two-segment piecewise-linear DP characteristic. With the appropriate choice of parameters, the piecewise-linear circuit model has a positive Lyapunov exponent. >
362 citations
05 Sep 1999
TL;DR: It is shown that synchronization in the Colpitts system is a result of stable error dynamics between the transmitter and receiver and is demonstrated using Lyapunov's theorem.
Abstract: In this paper, a synchronization of chaotic Colpitts oscillators with applications to binary communications is described. In this approach, the transmitter contains a chaotic Colpitts oscillator with a parameter that is modulated by an information signal. Each symbol to be transmitted is coded as an attractor in Colpitts oscillator. The receiver consists of a synchronous chaotic subsystem augmented with a low-pass filter, a circuit for addition and two multiplier circuits. A proof of the synchronization effect is demonstrated using Lyapunov's theorem. It is shown that synchronization in the Colpitts system is a result of stable error dynamics between the transmitter and receiver. Results of simulations are presented.
20 citations
04 Dec 2000
TL;DR: A CC scheme is proposed that represents an efficient solution in terms of complexity, power consumption, information transmission security, and performance and is realized by cascading two circuits, namely a nonlinear third order IIR filter and a modified Colpitts oscillator.
Abstract: The objective of this paper is to present a low-power realization of a Chaotic Communication (CC) system. We propose a CC scheme that represents an efficient solution in terms of complexity, power consumption, information transmission security, and performance. the newly proposed system is realized by cascading two circuits, namely a nonlinear third order IIR filter and a modified Colpitts oscillator. It is shown that the latter circuit behaves chaotically and the synchronization mechanism can be used to build a complete communication system. The experimental results show that, in terms of power dissipation, the scheme that we propose performs much better (about 2.5 times) compared to other implementations proposed so far for CC. Directions to further decrease the power consumption are suggested.
10 citations