A simulator has been developed for an ultrasound linear scan B-mode imaging system. First, a numerical method of calculating field patterns or pulse echo patterns is presented for a full-aperture system with a given transducer geometry in nonattenuating and attenuating media, based on the measured temporal impulse response for a single transducer element immersed in water, and taking into account the variation of attenuation and acoustic velocity in human tissue. The simulator then models and simulates the receiver subsystems in detail using the received pulse echo. In particular, a dynamic inverse filter, to improve the axial resolution, and an unconventional TGC gain function, to reduce the SNR deterioration through logarithmic compression, are proposed. Finally, simulation and experimental results are presented and discussed.