Publications by Ali Hormati | EPFL Graph Search

Fast and robust estimation of jointly sparse channels

Martin Vetterli, Ali Hormati, Yann Barbotin

A device and method for estimating multipath jointly sparse channels. The method comprises receiving a number K of signal components by a number P of receiving antennas, where P≧2. The method further comprises estimating the sparsity condition of the multi ...

2013

Estimation of Sparse MIMO Channels with Common Support

Martin Vetterli, Ali Hormati, Yann Barbotin

We consider the problem of estimating sparse communication channels in the MIMO context. In small to medium bandwidth communications, as in the current standards for OFDM and CDMA communication systems (with bandwidth up to 20 MHz), such channels are indiv ...

2012

ESTIMATING SPARSE MIMO CHANNELS HAVING COMMON SUPPORT

Martin Vetterli, Ali Hormati, Yann Barbotin

According to a first aspect of the present invention there is provided a method of estimating, jointly, a set of multipath channels having a common path support, the method comprising the steps of, estimating jointly the common path support of the set of m ...

USPTO2012

Sampling of Sparse Channels with Common Support

Martin Vetterli, Ali Hormati, Yann Barbotin

The present paper proposes and studies an algorithm to estimate chan- nels with a sparse common support (SCS). It is a generalization of the classical sampling of signals with Finite Rate of Innovation (FRI) and thus called SCS-FRI. It is applicable to OFD ...

2011

Estimating Sparse MIMO Channels Having Common Support

Martin Vetterli, Ali Hormati, Yann Barbotin

We propose an algorithm (SCS-FRI) to estimate multipath channels with Sparse Common Support (SCS) based on Finite Rate of Inno- vation (FRI) sampling. In this setup, theoretical lower-bounds are derived, and simulation in a Rayleigh fading environment show ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2011

Methods and apparatus for estimating a sparse channel

Martin Vetterli, Ali Hormati, Yann Barbotin

Embodiments include a method for sending a selected number of pilots (20) to a sparse channel having a channel impulse response limited in time comprising sending the selected number of the pilots (20). The pilots (20) are equally spaced in the frequency d ...

USPTO2011

Group Testing with Probabilistic Tests: Theory, Design and Application

Martin Vetterli, Amin Karbasi, Ali Hormati, Mahdi Cheraghchi Bashi Astaneh

Identification of defective members of large populations has been widely studied in the statistics community under the name of group testing. It involves grouping subsets of items into different pools and detecting defective members based on the set of tes ...

Institute of Electrical and Electronics Engineers2011

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

Martin Vetterli, Ali Hormati

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 ...

IEEE Institute of Electrical and Electronics Engineers2011

Robust Ultrasound Travel-time Tomography Using the Bent Ray Model

Martin Vetterli, Olivier Roy, Ali Hormati, Ivana Jovanovic

We present a bent ray reconstruction algorithm for an ultrasound tomography (UT) scanner designed for breast screening. The scanner consists of a circular array of transmitters and receivers which encloses the object to be imaged. By solving a nonlinear sy ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2010

Sound Speed Estimation Using Wave-based Ultrasound Tomography: Theory and GPU Implementation

Martin Vetterli, Olivier Roy, Ali Hormati, Ivana Jovanovic, Reza Parhizkar

We present preliminary results obtained using a time domain wave-based reconstruction algorithm for an ultrasound transmission tomography scanner with a circular geometry. While a comprehensive description of this type of algorithm has already been given e ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2010