Analysis of the data transportation multi-hop network for an intelligent environment

The recent advent of ambient intelligence is enabled by parallel technological advancements in sensing, context recognition, embedded systems and communications. This paper focuses on the communication issues of embedded systems, particularly the latency Quality of Service (QoS) metric and the multi-hop communications with Bluetooth standard, to examine the viability of communications of embedded systems in AmI environments and applications. Bluetooth is a worldwide radio license-free technology that enables the creation of low-power multi-hop networks interconnecting multiple devices. Bluetooth sets the procedure to establish piconets (point-to-point and point-to-multipoint links) and scatternets (multi-hop communications), and hence, Bluetooth nodes can be interconnected to form wireless networks. This paper presents research on multi-hop latency that was conducted using a custom-built test platform. Moreover, an empirical model is derived to calculate the latency over asynchronous links when links in scatternets are always active or in sniff mode. The designers of ambient intelligent devices and networks can take advantage of the model and the estimation of the delay in Bluetooth multi-hop networks presented in this paper.