Large range of tiny, embedded sensor devices capable of sensing, communicating and routing data are available now a days. Due to higher failure rate of sensor nodes or their mobility, the sink node might not exist in their transmission range. We proposed an approach which uses fuzzy logic to deal with diverse QoS requirements of sensor applications. In this paper, we have designed, an Intelligent Intermediate Robust Gateway module, which provides an efficient and consistent QoS based connectivity to sensor applications to outside world. This Gateway defines a decision structure needed by sensor network applications to switch over to any wireless network, in order to make communication with the remote sink fulfilling application QoS requirement.The result of our approach show that it is capable of selecting appropriate network for range of sensor network applications.