ART-Rx: A Proportional-Integral-Derivative (PID) Controlled Adaptive Real-Time Threshold Receiver for Molecular Communication

Diffusion-based molecular communication (MC) suffers from stochastic propagation, inter-symbol interference (ISI), and fast microfluidic variations. We present ART-Rx, an adaptive threshold receiver that embeds a proportional–integral–derivative (PID) controller on a system-on-chip and updates the decision boundary once per symbol. Simulations sweeping interferer density, CSK levels, flow, separation, diffusion, and binding kinetics show a mean bit-error ratio (BER) of 1.8×10-2; BER remains below 6.0×10-2 for -4 dB≤SNR≤19 dB and does not exceed 7.4×10-2 for transmitter–receiver separations up to 10-2 m. ART-Rx cuts BER by 2.6× relative to the best non-ML baseline and outperforms a statistical fixed-threshold detector while retaining O(1) operations per symbol. Ziegler–Nichols gain scheduling combined with integral wind-up protection preserves closed-loop stability across strongly non-linear regimes, positioning ART-Rx as a practical front-end for resource-constrained Internet-of-Bio-Nano-Things nodes and implantable biosensors.