Abstract : The aim of my thesis is to study the cosmic microwave background anisotropies observed by the Archeops experiment. Archeops is an experiment dedicated to the measurement of these anisotropies over a wide range of angular scales. The instrument is carried by a stratospheric balloon and is a test-bed experiment of the Planck satellite mission. I first describe the formation of the anisotropies and the information they provide on the Universe. I then describe the Archeops experiment: the instrument, its capabilities, and its scientific goals. My work in the Archeops collaboration centers on two topics. The first is the subtraction of signals which are sychronous with the gondola rotation, a prerequisite to any detector calibration on the cosmological dipole. The second topic is the anisotropy power spectrum reconstruction. I begin with an examination of origine of scan-synchronous effects and concentrate on atmosphere emission; I then describe some methods that I have developped to subtract these contributions. Two of these methods are applied to the data and provide a calibration of the detectors. To begin the second topic, I show how the anisotropy power spectrum can be reconstructed. I then show the validity of the power spectrum computation on the data. To determine the properties of the data, I have developped methods to evaluate the noise contribution on the power spectrum and to reduce galactic contamination. Finally the power spectrum reconstruction pipeline is fully tested with simulations based on properties of the actual data.