High-dimensional Variance based Logic for Reliable Communication at Near-zero Energy-per-bit

Abstract

In variance-based logic (VBL), information is encoded by the change in the variance of a signal as opposed to the conventional mean-based logic (MBL) where the information is encoded by the change in the mean of the signal. In this paper, we compare the fundamental limits on the minimum energy per bit that can be achieved by VBL and MBL representations in high-dimensional signal space. We show that while for MBL representations, the trade-off between the energy-per-bit and the bit-error-rate (BER) is fundamentally constrained by the classical Shannon-limit, using VBL representations it is theoretically possible to achieve arbitrarily small BER while dissipating near zero energy-per-bit. This surprising result has been experimentally verified for Additive-white-Gaussian-Noise (AWGN) channels using Monte-Carlo simulations. We believe that high-dimensional VBL based encoding could provide a new approach for designing ultra-energy-efficient communication and sensing systems.