Data aggregation is effective information processing method to solve energy saving problem of WSNs.Most existing data aggregation algorithm discuss fusion problem in the scene that the number of nodes is fixed.However

data transmission quantity is directly proportional to number of nodes. And the optimal energy-saving strategy should be that number of nodes which satisfy performance condition. Sequential detection is applied in WSNs data aggregation and math model is established. Taking into account attenuation of wireless channel and characters of physical layer moddemod

a WSNs data aggregation judge method based on sequential detection is proposed

and characters of WSNs data aggregation based on sequential detection（ WDASD） are tested by simulations.