Based on the analysis of the BLISS (bi-level integrated system synthesis)

an improved method of BLISS was proposed

and the response surface based on design of experiments was introduced to make an approximation in both the subsystem and the system-level meanwhile the parameters of moving step were set

making unnecessary for complex sensitivity analysis;the movement limits of each iterative optimization in the BLISS method

and the optimization iterations and the possibility of falling into local optimum were reduced.Finally

two specific examples were given to verify above method compared with traditional BLISS.The results show that the optimization iterations of above methods were respectively reduced by 57.9% and 70.3%

respectively.