The purpose of the functional analysis and allocation
activity is to clearly describe the system functionality, divide functions into sub-functions and to allocate them appropriately to subsystems (INCOSE, 2004). As shown in Figure 1, functional
analysis and allocation is based on input provided by requirements analysis, which also receives
feedback via the requirements loop from functional analysis and allocation. Furthermore,
functional analysis and allocation also provides input to design synthesis and receives feedback
through the design loop.