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The purpose of this work is to demonstrate the possibility of expanding the radiation pattern in a hydroacoustic parametric antenna using an intra-pulse scan with an acoustic beam. Experience in the development and testing of parametric antennas has shown that the most efficient generation of differential frequency waves can be achieved by emitting narrow beams a few degrees wide at the maximum power of the pump antenna. A further increase in the width of the radiation pattern at the same operating frequencies leads to a drop in the level of the pump signals and a decrease in the length of the nonlinear interaction zone, and therefore to a significant decrease in the signal of the difference frequency. It is possible to expand the radiation pattern, while maintaining the size of the radiating surface of the antenna and the level of the emitted signal, using intrapulse scanning. Intra-pulse scanning was performed by sequential radiation of short pulses with rotation of the antenna pattern in the scanning plane. To conduct experimental studies, a hydroacoustic parametric radiating system was developed, consisting of a multichannel pumping antenna and power amplifier-generator modules. Experimental studies were carried out on a unique scientific installation "Imitation-natural hydroacoustic complex" SFU. Measurements were made of the parametric antenna radiation patterns at the difference frequency. Using the proposed method, it was possible to increase the width of the main maximum of a parametric antenna by about 2 times. The work shows the change in the envelope of the emitted signal, depending on the direction of radiation. Experimental studies have shown the fundamental possibility of expanding the radiation pattern of a parametric antenna with the help of intrapulse scanning with an acoustic beam at a constant size of the radiated surface of the pump antenna