The hardware platform is the static, unchanging portion of your hardware design. It includes the Xilinx support archive (XSA) file exported from the Vivado Design Suite. The hardware platform describes platform hardware setup and the acceleration resources that can be used by acceleration applications; for example, input and output interfaces, clocks, and AXI buses. The Vitis tool builds on top of the platform to connect up your PL kernels and AI Engine design.
The XSA for the beamforming tutorial is generated by the vivado command:
vivado -mode batch -source vck190_v1_0_xsa.tcl -tclargs xcvc1902-vsva2197-2MP-e-S