Inexact Arithmetic Circuits for Energy Efficient IoT Sensors Data Processing

Developing portable autonomous systems is highly requested for numerous application domains such as Internet of Things (IoT), wearable devices, and biomedical applications. Portable systems usually contain autonomous and networked sensors; each sensor hosts multiple input channels (e.g. tactile) closely coupled to embedded computing unit and power supply. The embedded computing unit should locally extract meaningful information by employing sophisticated methods. This imposes challenges on real time operation and adds a burden regarding power consumption. Approximate or inexact computing represents a promising solution for energy efficient data processing; it tunes the accuracy of computation on the specific application requirements in order to reduce power consumption. In this paper, inexact arithmetic circuits have been employed to improve the energy efficiency for sensors digital data processing. The proposed inexact circuits achieve up to 80% power saving when compared to the exact one, and similar solutions presented in literature with a maximum loss of 1.39 dB in output SNR when applied to FIR filters.