We present middle-atmospheric ozone mixing ratio profiles obtained from measurements around 142 GHz using the ground-based millimeter wave radiometer (MIRA 1) developed at the Forschungszentrum Karlsruhe. Data were recorded during spring season of 1994 from the summit of Hornisgrinde (1165 m, 48.61 ¿N, 8.20 ¿E), Germany. They were severely disturbed by standing waves caused by reflections in the internal transmission path. The profiles are retrieved by using a new extension of the well-known constrained linear inversion and optimal estimation method, respectively. With this new extension both techniques are capable of fitting the amplitudes and phases of standing waves in the inversion algorithm itself rather than during preprocessing. In the present paper, analysis of the retrieval technique is given, including a short analysis of sources of error. The new retrieval technique proves to be a reliable tool for the inversion of measured spectra disturbed by standing waves.¿ 1997 American Geophysical Union