CHAOS COMMUNICATION OVER NOISY CHANNELS

2000 ◽  
Vol 10 (04) ◽  
pp. 719-735 ◽  
Author(s):  
MARTIN HASLER ◽  
THOMAS SCHIMMING
Keyword(s):  
White Noise ◽  
Discrete Time ◽  
Communication Systems ◽  
Gaussian White Noise ◽  
Time Base ◽  
Digital Information ◽  
Noise Perturbation ◽  
Chaos Communication ◽  
Shift Keying ◽  
Chaos Shift Keying

The problem of transmitting digital information using chaotic signals over a channel with Gaussian white noise perturbation is introduced rigorously. It is shown that discrete time base-band chaotic communication systems with discrete time Gaussian white noise in the channel are sufficiently general in this context. The optimal receiver is given explicitly in terms of conditional probabilities. For the example of chaos shift keying using iterations of the tent map, the optimal classifier is constructed explicitly. Finally, it is shown how previously published methods, in particular those based on chaos synchronization, fit into this framework.

APPROXIMATE-OPTIMAL DETECTOR FOR CHAOS COMMUNICATION SYSTEMS

2003 ◽  
Vol 13 (05) ◽  
pp. 1329-1335 ◽  
Author(s):  
FRANCIS C. M. LAU ◽  
CHI K. TSE
Keyword(s):  
Communication Systems ◽  
Computational Effort ◽  
Detection Technique ◽  
Optimal Detection ◽  
Error Performance ◽  
Spreading Factor ◽  
Chaos Communication ◽  
Optimal Detector ◽  
Shift Keying ◽  
Chaos Shift Keying

Recently, an optimal noncoherent detection technique for chaos-shift-keying digital communication system has been proposed. The computational intensity required, however, increases exponentially with the spreading factor. In this Letter, we propose an approximate-optimal detection technique, whose computational effort increases only linearly with the spreading factor. In particular, we use the chaotic sequences generated by a skew tent map as an example to illustrate the approximate-optimal detection method. The bit error performance of the proposed detector is evaluated by computer simulations and the results are compared with those obtained using the optimal detector.

scholarly journals Efficient error correcting scheme for chaos shift keying signals

2019 ◽  
Vol 9 (5) ◽  
pp. 3550
Author(s):  
Hikmat N. Abdullah ◽  
Thamir R. Saeed ◽  
Asaad H. Sahar
Keyword(s):  
Error Correction ◽  
Logistic Map ◽  
Chaotic Sequence ◽  
Chaos Communication ◽  
Shortest Distance ◽  
Correction Scheme ◽  
Shift Keying ◽  
Minimum Delay ◽  
Modified Logistic Map ◽  
Chaos Shift Keying

An effective error-correction scheme based on normalized correlation for a non coherent chaos communication system with no redundancy bits is proposed in this paper. A modified logistic map is used in the proposed scheme for generating two sequences, one for every data bit value, in a manner that the initial value of the next chaotic sequence is set by the second value of the present chaotic sequence of the similar symbol. This arrangement, thus, has the creation of successive chaotic sequences with identical chaotic dynamics for error correction purpose. The detection symbol is performed prior to correction, on the basis of the suboptimal receiver which anchors on the computation of the shortest distance existing between the received sequence and the modified logistic map’s chaotic trajectory. The results of the simulation reveal noticeable Eb/No improvement by the proposed scheme over the prior to the error- correcting scheme with the improvement increasing whenever there is increase in the number of sequence N. Prior to the error-correcting scheme when N=8, a gain of 1.3 dB is accomplished in E<sub>b</sub>/N<sub>o</sub> at 10<sup>-3 </sup>bit error probability. On the basis of normalized correlation, the most efficient point in our proposed error correction scheme is the absence of any redundant bits needed with minimum delay procedure, in contrast to earlier method that was based on suboptimal method detection and correction. Such performance would render the scheme good candidate for applications requiring high rates of data transmission.

Encryption of Analog and Digital signals through Synchronized Chaotic Systems

2011 ◽  
pp. 415-438
Author(s):  
Kehui Sun
Keyword(s):  
Secure Communication ◽  
Communication Systems ◽  
Chaotic Sequence ◽  
Digital Signals ◽  
Encryption Schemes ◽  
Shift Keying ◽  
Chaos Shift Keying ◽  
Sequence Generator ◽  
Chaotic Secure Communication ◽  
Spreading Spectrum

Chaos is characterized by aperiodic, wideband, random-like, and ergodicity. Chaotic secure communication has become one of the hot topics in nonlinear dynamics since the early 1990s exploiting the technique of chaos synchronization. As distinguished by the type of information being carried, chaos-based communication systems can be categorized into analogy and digital, including four popular techniques such as Chaos Masking, Chaos Shift Keying, Chaos Modulation, and Chaos Spreading Spectrum. In this chapter, the principles of these schemes and their modifications are analyzed by theoretical analysis as well as dynamic simulation. In addition, chaos-based cryptography is a new approach to encrypt information. After analyzing the performances of chaotic sequence and designing an effective chaotic sequence generator, the authors briefly presented the principle of two classes of chaotic encryption schemes, chaotic sequence encryption and chaotic data stream encryption.

scholarly journals Filtering with a limiter

1998 ◽  
Vol 11 (3) ◽  
pp. 289-300 ◽  
Author(s):  
R. Liptser ◽  
P. Muzhikanov
Keyword(s):  
Weak Convergence ◽  
Diffusion Process ◽  
White Noise ◽  
Discrete Time ◽  
Diffusion Approximation ◽  
Conditional Expectation ◽  
Gaussian White Noise ◽  
Sampling Step ◽  
Non Gaussian ◽  
Filtering Problem

We consider a filtering problem for a Gaussian diffusion process observed via discrete-time samples corrupted by a non-Gaussian white noise. Combining the Goggin's result [2] on weak convergence for conditional expectation with diffusion approximation when a sampling step goes to zero we construct an asymptotic optimal filter. Our filter uses centered observations passed through a limiter. Being asymptotically equivalent to a similar filter without centering, it yields a better filtering accuracy in a prelimit case.

The exact bispectra for bilinear realizable processes with hermite degree 2

1991 ◽  
Vol 23 (04) ◽  
pp. 798-808 ◽  
Author(s):  
György Terdik ◽  
Laurie Meaux
Keyword(s):  
White Noise ◽  
Discrete Time ◽  
Hermite Polynomial ◽  
Transfer Functions ◽  
Gaussian White Noise ◽  
Second Order ◽  
Bilinear Model ◽  
White Noise Process ◽  
Noise Process ◽  
Gaussian White Noise Process

This paper deals with the stationary bilinear model with Hermite degree 2 in discrete time which is built up by the first- and second-order Hermite polynomial of a Gaussian white noise process. The exact spectrum and bispectrum is constructed in terms of the transfer functions of the model.

The exact bispectra for bilinear realizable processes with hermite degree 2

1991 ◽  
Vol 23 (4) ◽  
pp. 798-808 ◽  
Author(s):  
György Terdik ◽  
Laurie Meaux
Keyword(s):  
White Noise ◽  
Discrete Time ◽  
Hermite Polynomial ◽  
Transfer Functions ◽  
Gaussian White Noise ◽  
Second Order ◽  
Bilinear Model ◽  
White Noise Process ◽  
Noise Process ◽  
Gaussian White Noise Process

This paper deals with the stationary bilinear model with Hermite degree 2 in discrete time which is built up by the first- and second-order Hermite polynomial of a Gaussian white noise process. The exact spectrum and bispectrum is constructed in terms of the transfer functions of the model.

PERFORMANCE OF FREQUENCY-MODULATED DIFFERENTIAL-CHAOS-SHIFT-KEYING COMMUNICATION SYSTEM OVER MULTIPATH FADING CHANNELS WITH DELAY SPREAD

2005 ◽  
Vol 15 (12) ◽  
pp. 4027-4033 ◽  
Author(s):  
YONGXIANG XIA ◽  
CHI K. TSE ◽  
FRANCIS C. M. LAU ◽  
GÉZA KOLUMBÁN
Keyword(s):  
Fading Channels ◽  
Communication System ◽  
Communication Systems ◽  
Multipath Fading ◽  
Equivalent Model ◽  
Delay Spread ◽  
Error Performance ◽  
Multipath Fading Channels ◽  
Shift Keying ◽  
Chaos Shift Keying

Multipath performance is an important consideration for chaos-based communication systems. In this letter, the performance of the FM-DCSK communication system over multipath fading channels is evaluated by computer simulations. Both Rayleigh fading and Ricean fading are considered, and the low-pass equivalent model of the FM-DCSK system is used in the simulation. Based on this model, we analyze the bit error performance of the system and the effects of system parameters on the bit-error performance.

Sign in / Sign up

Export Citation Format

Share Document