This paper proposes a speech dereverberation method based on the MTF concept. This method can be used without measuring the impulse response of room acoustics. In the model, the power envelopes and carriers are decomposed from a reverberant speech signal using an N -channel filterbank and then are dereverberated in each respective channel. In the envelope dereverberation process, a power envelo...

In this paper, a state and unknown input observer is proposed for discrete-time linear systems with bounded unknown inputs and measurement disturbances. The design procedure is formulated using a set of linear matrix inequalities, and leverages delayed (or fixed-lag) estimates. The observer error states and/or user-defined performance outputs are guaranteed to operate at pre-specified performan...

In this paper we study the problem of tracking a reference signal from the H" point, of view. As opposed to general Woo problems, whcrc only suboptimal solutions are obtained, wc show that for both the full information arid measurement, feedback tracking problems the H""-optimal solutions can be explicitly found. The results also indicate an interesting dichotomy between minimum phase and non-m...

This paper addresses the global asymptotic stabilization of nonlinear systems in the presence of unmodeled dynamics appearing at the input. The unmodeled dynamics are restricted to be minimum-phase and relative degree zero. On the basis of nonlinear small-gain arguments, we design a static feedback control law to achieve global asymptotic stabilization. In the absence of full state information ...

We consider the problem of output regulation for the class of minimum-phase nonlinear systems described in normal form. We assume that the ideal steady state control input fulfills a nonlinear regression law that is linearly parametrized in the uncertain parameters and we propose an internal model-based design that combines high-gain and identification tools. The identification tool by which th...

December 13-15, 2007: Firenze, Italy, ed. by C. Manfredi, ISBN 978 88-8453-673-3 (print) ISBN 978-88-8453-674-7 (online) © Firenze university press, 2007. Abstract: Nowadays an ever increasing interest in voice studies is present in the research and application fields both under biomedical and bioengineering scopes. Everyday more resources are assigned to this research field looking for new met...

This paper presents a new approach towards the design of iterative learning control (Moore, 1993). In linear motion control systems the design is often complicated by the inverse plant sensitivity being non-causal and even unstable. To overcome these problems the inverse system is split up in a causal and a non-causal part. We apply high-performance differentiating filters together with a mixed...

This paper presents an improved method for asynchronous embedding and recovery of sub-audible watermarks in speech signals. The watermark, a sequence of DTMF tones, was added to speech without knowledge of its time-varying characteristics. Watermark recovery began by implementing a synchronized zero-phase inverse filtering operation to decorrelate the speech during its voiced segments. The fina...

A control design to stabilise a reduced scale autonomous helicopter equipped with a camera is presented. The proposed algorithm is motivated by recent work in image-based visual servoing control for under-actuated dynamic systems. This work is extended by considering models that contain weakly nonminimum phase zero dynamics. This is an important class of systems since an o set between the camer...

Scattering of teleseismic body waves is conventionally used to investigate crustal and mantle structure using the so-called “receiver function” technique. This approach makes use of the fact that teleseismic events have nearvertical incidence upon horizontally layered structure, ensuring minimum phase, and assumes that source-time functions can be approximated by energy on the P component of mo...