In　this　paper,　we　design　a　standardized　DBF　(Digital　Beam　Forming)　module　based　on　multi-level　FPGA　that　can　cascade　and　expand.　This　multi-level　FPGA　is　used　to　implement　multi-level　synthesis　calculation　of　96　optical　fibers　for　enhancing　the　processing　capability　and　the　speed　of　single-board　module　beam　synthesis.　Furthermore,　a　cascadeable　and　scalable　DBF　system　based　on　the　VPX　platform　is　designed　by　DBF　module.　For　improving　the　efficiency　of　data　exchange　in　the　entire　system,　a　PCI　Express　to　Serial　Rapid　IO　communication　network　(PSCN)　is　proposed　to　carry　out　one-to-one　or　one-to-many　communication　between　the　host　computer　and　multiple　FPGAs.　Finally,　the　DBF　module　has　been　built　for　testing　of　large-scale　digital　phased　array　antennas　(DPAAs).　©　2020　IEEE.