Usually acoustic beamformer or directive microphones are used in order to focus on known potential locations emitting sounds so as to identify and extract their major noise components. However performances of these techniques depend on the number of microphones and the a priori knowledge of the source locations. Based on the measurement of phase delays between sensors and short-time Fourier transform of the sound field, we present an algorithm for localise and extract harmonic sound sources by merging goniometric and beamforming approach. The acoustic goniometer is composed of a small array of microphones and permits to detect and identify more sources than the number of available microphones. In order to evaluate the performance of this system, an experiment is performed with a planar antenna composed by four omnidirectional microphones laid out in front of eight loudspeakers located in the horizontal plane. We describe the experiment performed in an anechoic chamber.