Publications by Martin Vetterli

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When is uncoded transmission optimal? This paper derives easy-to-check necessary and sufficient conditions that do not require finding the rate-distortion and the capacity-cost functions. We consider the symbol-by-symbol communication of discrete-time memoryless sources across discrete-time memoryless channels, using single-letter coding and decoding. This is an optimal communication system if and only if the channel input cost function and the distortion measure can be written in a form that we explicitly

This paper studies the problem of sound source localization in a distributed wireless sensor network formed by mobile general pur- pose computing and communication devices with audio I/O capa- bilities. In contrast to well understood localization methods based on dedicated microphone arrays, in our setting sound localization is performed using a sparse array of arbitrary placed sensors (in a typical scenario, localization is performed by several laptops/PDAs co-located in a room). Therefore any far-field as

We consider the problem of designing low-complexity digital receivers for CDMA systems operating over channels with single or multiple propagation paths. We specifically exploit a finite rate of innovation property of CDMA signals and develop a method that leads to an efficient solution of the combined problem of multipath channel estimation and signal detection from a low-dimensional subspace of a received signal. Unlike existing schemes that typically resort to chip rate sampling and manipulate with large

Recent sampling results enable the reconstruction of signals composed of streams of fixed-shaped pulses. These results have found applications in topics as varied as channel estimation, biomedical imaging and radio astronomy. However, in many real signals, ...

The various types of advanced television (ATV) are defined, and the most advanced type, high-definition TV (HDTV), is discussed. The present status of HDTV development in the US, Japan, and Europe is examined. Signal processing requirements for HDTV are briefly considered, and the benefits of and prospects for all-digital HDTV are explored. Video compression techniques, implementation issues, and the future of HDTV are also discussed

We propose a new image device called gigavision camera. The main differences between a conventional and a gigavision camera are that the pixels of the gigavision camera are binary and orders of magnitude smaller. A gigavision camera can be built using stan ...

In recent years, wavelet-based algorithms have been successful in different signal processing tasks. The wavelet trans- form is a powerful tool because it manages to represent both tran- sient and stationary behaviors of a signal with few transform coeffi- cients. Discontinuities often carry relevant signal information, and therefore, they represent a critical part to analyze. In this paper, we study the dependency across scales of the wavelet coefficients generated by discontinuities. We start by showing t

We study the spatial-temporal sampling of a linear diffusion field, and show that it is possible to compensate for insufficient spatial sampling densities by oversampling in time. Our work is motivated by the following issue often encountered in sensor net ...

In sensor networks and communication systems, one is often confronted with sampling multiple sparse signals having a common support set. Multipath channels in a multiple-input multiple-output (MIMO) wireless communication setting is an interesting example ...

It is shown that infinite impulse response (IIR) filters lead to more general wavelets of infinite support than finite impulse response (FIR) filters. A complete constructive method that yields all orthogonal two channel filter banks, where the filters have rational transfer functions, is given, and it is shown how these can be used to generate orthonormal wavelet bases. A family of orthonormal wavelets that have a maximum number of disappearing moments is shown to be generated by the halfband Butterworth f

The present invention concerns a method of method of relighting a media item comprising media elements. The method comprises, for at least some of the media elements: determining, in a first signal domain, a light transport function describing the appearan ...

Acoustic source localization often relies on the free-space/far-field model. Recent work exploiting spatio-temporal sparsity promises to go beyond these scenarios, however, it requires the knowledge of the transfer functions from each possible source locat ...

We consider the problem of low-complexity timing synchronization in digital receivers for DS-CDMA and UWB systems operating over channels with single or multiple propagation paths. We extend some of our recent sampling results for certain classes of non-bandlimited signals and develop a method that takes advantage of transform techniques to perform propagation delay estimation from a low-dimensional subspace of a received signal, that is, by sampling below the Nyquist rate. By lowering the sampling rate we

In opportunistic routing, each node maintains a group of candidate relays to reach a particular destination, and transmits packets to any node in this group. If a single candidate relay receives the packet, it becomes the effective relay to forward the packet further. If no candidate receives the packet, then the current sender re-transmits. If multiple candidates receive the packet, then the link layer chooses a single receiver to be the relay. This choice could be made at random, or it could be driven by

We consider the problem of multiple-loudspeaker low-frequency room equalization for a wide listening area, where the equalized loudspeaker is helped using the remaining ones. Using a spatial discretization of the listening area, we formulate the problem as ...

This paper highlights the possible tradeoffs between arithmetic and structural complexity when computing cyclic convolution of real data in the transform domain. Both Fourier and Hartley-based schemes are first explained in their usual form and then improved, either from the structural point of view or in the number of operations involved. Namely, we first present an algorithm for the in-place computation of the discrete Fourier transform on real data: a decimation-in-time split-radix algorithm, more compac

Sensors acquire data, and communicate this to an interested party. The arising coding problem is often split into two parts: First, the sensors compress their respective acquired signals, potentially applying the concepts of distributed source coding. Then, they communicate the compressed version to the interested party, the goal being not to make any errors. This coding paradigm is inspired by Shannon’s separation theorem for point-to-point communication, but it leads to suboptimal performance in general n

SensorScope is a turnkey solution for environmental monitoring systems, based on a wireless sensor network and resulting from a collaboration between environmental and network researchers. Given the interest in climate change, environmental monitoring is a ...

Lensless cameras relax the design constraints of traditional cameras by shifting image formation from analog optics to digital post-processing. While new camera designs and applications can be enabled, lensless imaging is very sensitive to unwanted interfe ...

Distributed estimation of an unknown signal is a common task in sensor networks. The scenario usually envisioned consists of several nodes, each making an observation correlated with the signal of interest. The acquired data is then wirelessly transmitted ...

Martin Vetterli

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To Code, Or Not To Code: On the Optimality of Symbol-by-Symbol Communication

Acoustic Source Localization in Distributed Sensor Networks

Digital DS-CDMA receiver working below the chip rate: theory and design

Sampling and Exact Reconstruction of Pulses with Variable Width

Television by the bit

The Gigavision Camera

Wavelet Footprints: Theory, Algorithms and Applications

Spatial Super-Resolution of a Diffusion Field by Temporal Oversampling in Sensor Networks

Compressive Sampling of Multiple Sparse Signals Having Common Support Using Finite Rate of Innovation Principles

Wavelets and recursive filter banks

Media item relighting technique

Room Helps: Acoustic Localization With Finite Elements

High-Resolution Acquisition Methods for Wideband Communication Systems

Least-Cost Opportunistic Routing

Multi-channel low-frequency room equalization using perceptually motivated constrained optimization

Improved Fourier and Hartley transform algorithms: application to cyclic convolution of real data

Source-Channel Communication in Sensor Networks

SensorScope: Application-Specific Sensor Network for Environmental Monitoring

Let There Be Light: Robust Lensless Imaging Under External Illumination With Deep Learning

Dimensionality Reduction for Distributed Estimation in the Infinite Dimensional Regime