In this paper, we detail a new method that allows measuring simultaneously distance and orientation of a flat horizontal or vertical surface (e.g. wall, flat bottom) with a single acoustic transducer. A single mono-frequency ping is neces-sary. Then the analysis of the peaks in the received echo is sufficient to find out both distance and orientation. This method does not require any a priori knowledge of the target backscattering properties. Its advantages are: a very high sampling rate, the smallest and cheapest sensor, and low acoustic interferences with other acoustic devices (single frequency, short ping). We present theoretical aspect, simulation results, and experiments.