A 1000+ Channel Bionic Communication System

The wireless electronic nervous system interface known as the Functional Electrical Stimulation-Battery Powered bion® System is being developed at the Alfred Mann Foundation. It contains a real-time propagated wave micro- powered multichannel communication system (1). This system is designed to send bi-directional messages between an external Master Controller Unit (MCU), and each one of a group of injectable stimulator-sensor battery powered bion® implants (BPB). The system is capable of communicating in each direction about 90 times per second using a structure of 850 time slots within a repeating 11 millisecond time window. The system's total Time Division Multiple Access (TDMA) communication capability is about 77,000 two-way communications per second on a single 5MHz wide radio channel. Each time slot can be used by one BPB, or shared alternately by two or more BPBs. Each bidirectional communication consists of a 15 data bit message sent from the MCU sequentially to each BPB and 10 data bit message sent sequentially from each BPB to the MCU. Redundancy bits are included to provide error detection and correction. This communication system is designed to draw only a few microamps from the 3.6 volt, 3.0 mAHr Lithium Ion (LiIon) battery contained in each BPB, and the majority of the communications circuitry is contained within a 1.4 x 5 mm integrated circuit.