Francis Chung-Ming Lau

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The performance of the noncoherent differential chaos-shift-keying (DCSK) communication system over a multipath fading channel with delay spread is evaluated. Analytical expressions of the bit error rates are derived under the assumption of an independent Rayleigh fading two-ray channel model. Analytical and simulated results are presented and compared. The(More)
In this paper, exact analytical expressions for the bit error rates (BERs) in a multiple-access chaos-based digital communication system are derived. Comparisons are made with those obtained using traditional approximation methods which assume a Gaussian distribution for the conditional decision parameter. The obtained results are compared to the results of(More)
In this paper, we study a decode-and-forward twoway relaying network. We propose an opportunistic two-way relaying (O-TR) scheme based on joint network coding and opportunistic relaying. In the proposed scheme, one single “best relay” is selected by MaxMin criterion to perform network coding on two decoded symbols sent from two sources, and then to(More)
Both the inherently wideband differential-chaosshift-keying (DCSK) modulation and the space-time block code (STBC) are techniques that can mitigate the effect of multipath fading. By applying STBC at the chaotic segment level, a novel analog STBC-DCSK scheme is proposed in this paper. The proposed scheme is a simple configuration that combines the(More)
This paper studies the performance of selected chaos-based communication systems whose spectrum overlaps with that of conventional narrowband systems. Such a scenario may occur in normal practice when chaos-based systems are introduced while the conventional systems are still in operation. The particular chaos-based systems under study are the coherent(More)
The buck converter has been known to exhibit chaotic behavior in a wide parameter range. In this paper, the resonant parametric perturbation method is applied to control chaos in a voltage-mode controlled buck converter. In particular, the effects of phase shift and frequency mismatch in the perturbing signal are studied. It is shown that the control power(More)
In this paper, a multiple access (MA) technique is proposed for chaos-based communication systems, in which chaotic reference signals are transmitted followed by the information-bearing signals. Chaotic reference signals modulated by a binary training sequence are sent periodically. The same chaotic signals are then modulated by the binary data and(More)