Gravitational waves generated by coalescing binary systems of neutron stars or black holes are expected to behave like chirps, i.e. amplitude and frequency modulated signals, buried into strongly correlated noise, with very low signal to noise ratio. This note presents a wavelet based algorithm for on line processing and detection of such signals, from interferometric detectors which are currently being constructed , and discusses a few examples. The details of the method and more complete simulations can be found in [6]. The detection of gravitational waves, predicted by general relativity but never observed so far, is a major challenge in today's experimental physics. Several projects are currently being developed, among which one may quote the LIGO [1], GEO [4] and VIRGO [2] laser in-terferometric detectors. Among the potential sources for gravitational waves, the most promising are presumably pulsars, and coalesc-ing binary systems of black holes or neutron stars. Such systems are expected to produce " simple " signals, for which available models are considered reliable. We focus here on the case of coalescing binary systems. The corresponding gravitational waves take the form of chirps, i.e. amplitude and frequency modulated signals. The detection problem may be formulated as follows. The signal takes the form f (x) = h θ (x − x 0) + n(x) (1)