A mathematical model considering reflection as a reradiation phenomenon has been constructed. The model allows computation of the spectrum and waveform of a reflected pulse in terms of the incident plane‐wave pulse or its spectrum, the reradiation characteristics of the reflector, the incident direction, and the reradiation direction. Bottom reflection of sonic pulses in an isovelocity medium has been considered in terms of this model and temporal and spectral distortions have been calculated. The theory of Cron and Nuttall [J. Acoust. Soc. Am.37, 486–492 (1965)] is shown to be a special case of the present theory.