Decode-and-Forward Relay in Diffusion-based Molecular Communication Systems: Theory and Hardware Testbed

In diffusion-based molecular communication (MC), information transmit is governed by diffusion through a fluid medium. The transmission distance is limited by the attenuation process of the diffusion. To extend the transmission range, the relaying is used in the molecular communications recently. The decode-and-forward (DF) strategy is decode the received information then re-encode it to send which can reduce the accumulation of noise. In this paper, the state-of-the-art DF relaying is comprehensively surveyed. Considering the urgent situation to deploying the hardware testbed, based on the corresponding theoretical model, this article introduces a hardware testbed that is built to validate the superiority of the relay channels, where the DF strategy is adopted and the molecular concentration is served as the information carrier. Relevant results show that the DF relay channel can significantly improve the performance of diffusion based MC than the direct transmission channel