In this paper we report on a wireless optical communication system designed for biomedical applications like the transcutaneous optical biotelemetry links in brain machine interfaces. The system employs an optical UWB pulsed coding architecture that allowed to achieve data rate up to 300 Mbps. With respect to the state-of-the-art of these systems, the proposed solution makes use of sub-nanosecond laser pulses to obtain very high bit rate transmissions together with an overall reduced power consumption. The transmitter contains a pulsed semiconductor laser and the receiver a fast response time Si photodiode. The analogue laser driver and the photodiode conditioning circuit have been fabricated by using commercially available discrete components. In particular, the laser driver produces the current signals needed to generate the laser pulses while the photodiode readout circuit converts the photo-generated current pulses into voltage pulses by maintaining unaltered the system effective frequency response and the time domain characteristics. On the other hand, an FPGA board has been employed to implement the digital blocks that allow for the data coding/decoding and for the data pre- and post-processing procedures. A series of experimental measurements have been accomplished for a complete characterization of the proposed system by using a dermal sample of cleaned porcine skin located between the transmitter and the receiver. The communication system has been able to operate at data rates up to 300 Mbps with a BER lower than $10^10$ and a power consumption less than 37 pJ/bit.
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