Inria / Raweb 2004
Project-Team: DaRT

Search in Activity Report, year 2004:


Project-Team : dart

Section: Application Domains

Keywords: telecommunications, multimedia.

Intensive Signal Processing

The DaRT project aims to improve the design of embedded systems with a strong focus on intensive signal processing applications.

This application domain is the most intensive part of signal processing, composed of:

Many signal and image processing applications follow this organisation: software radio receiver, sonar beam forming, or JPEG 2000 encoder/decoder.

In the frame of the ModEasy project, we will also study computation intensive automotive safety embedded systems.

The systematic signal processing is the very first part of a signal processing application. It mainly consists of a chain of filters and regular processing applied on the input signals independently of the signal values. It results in a characterization of the input signals with values of interest.

The intensive data processing is the second part a of a signal processing application. It applies irregular computations on the values issued by the systematic signal processing. Those computations may depend on the signal values.

Below are three example applications from our industrial partners.

Software Radio Receiver

This emerging application is structured in a front end systematic signal processing including signal digitalization, channel selection, and application of filters to eliminate interferences. These first data are decoded in a second and more irregular phase (synchronization, signal demodulation...).

Sonar Beam Forming

A classical sonar chain consists in a first and systematic step followed by a more general data processing. The first step provides frequency and location correlations (so called beam) from a continuous flow of data delivered by the hydrophones (microphones disposed around a submarine). It is based on signal elementary transformations: FFT (Fast Fourrier Transformation) and discrete integration. The second step analyses a given set of beams and their history to identify temporal correlation and association to signal sources.

JPEG-2000 Encoder/Decoder

JPEG-2000 is a new standard format for image compression. The encoder works in a two-steps approach [26]. The first part (from preprocessing to wavelet decomposition) is systematic. The second part of the encoder includes irregular processing (quantification, two coding stages). The decoder works the other way around: a first irregular phase is followed by a systematic phase.