An original solution for Bluetooth wireless synchronous communication dedicated to a sensors and actuators system

For low cost wireless data acquisition provided from some sensors, Bluetooth asynchronous links (ACL) on HCI interface are suited to use. However, when the transducers sampled system is submitted to stricter time constraints, a solution where data crosses a minimum software and firmware layers is necessary. In this way, we investigated the PCM interface dedicated to the voice. This paper shows how, using PCM interface, with the choice of logarithmic laws and the conception of a particular coding/decoding circuit, the synchronous Bluetooth links (SCO) allow digital data conservation and offer a reduced and stationary transmission delay. Our practical readings taken and comparison on the synchronous and asynchronous transmission latency have allowed proposing a new architecture, which can cover a large variety of wireless communicating sensors/actuators systems as well as short-range robotic applications.