Abstract Digital deconvolution of ultrasonic echo signals improves resolution and the quality of ultrasonic images. The Homomorphic deconvolution technique under noisy conditions is applied to simulation results in an ultrasonic pulse–echo amplitude scan line. The simulation includes radiation coupling and transducer response, as well as frequency-dependent absorption in the field medium. An accurate method of estimating the pulse-shaping effects of the transducer and the test medium are developed by using Homomorphic filtering. Experimental results are given which confirm the modelling.