Abstract
In this paper, a novel Memory-Assisted Adaptive-Threshold detection (MAAT) scheme for diffusion-based molecular communications (MC) systems is proposed. The proposed scheme applies to MC systems in which single-type of molecules is assumed to carry the information from the transmitting nano-machine, through a fluid medium, to the receiving nano-machine. The information is represented by the received concentration of the information molecules. We consider a single transmitter (Tx) and receiver (Rx) problem, where the communication takes place in a three-dimensional free-flow diffusion-based unbounded propagation environment. We present a novel adaptive-threshold detection algorithm suitable for binary On-OFF Keying (BOOK signaling), where the Rx adapts the 1/0 bit detection threshold based on past received bits. The adjustment of the 1/0 detection threshold based on past received bits helps to alleviate the inter-symbol interference resulting from residual (tail) diffusion molecules arriving at the receiver due to past bit transmissions and noise molecules. Performance evaluation shows a promising improvement in the un-coded BER performance of our proposed scheme compared with the traditional Fixed-Threshold Detection (FTD) approach. In addition, our proposed approach delivers BER levels comparable with considerably more complex approaches found in the literature.