Hypervector Design for Efficient Hyperdimensional Computing on Edge Devices

Toygun Basaklar, Yigit Tuncel, Shruti Yadav Narayana, Suat Gumussoy, Umit Y. Ogras

Keywords: Hyperdimensional computing, low-power learning algorithm, optimization

TL;DR: This paper presents a hypervector design technique for efficient hyperdimensional computing. It aims to achieve high accuracy and robustness with smaller dimensions while significantly reducing energy consumption and computational resources.

Abstract: Hyperdimensional computing (HDC) has emerged as a new light-weight learning algorithm with smaller computation and energy requirements compared to conventional techniques. In HDC, data points are represented by high dimensional vectors (hypervectors), which are mapped to high dimensional space (hyperspace). Typically, a large hypervector dimension ($\geq1000$) is required to achieve accuracies comparable to conventional alternatives. However, unnecessarily large hypervectors increase hardware and energy costs, which can undermine their benefits. This paper presents a technique to minimize the hypervector dimension while maintaining the accuracy and improving the robustness of the classifier. To this end, we formulate hypervector design as a multi-objective optimization problem for the first time in the literature. The proposed approach decreases the hypervector dimension by more than $128\times$ while maintaining or increasing the accuracy achieved by conventional HDC. Experiments on a commercial hardware platform show that the proposed approach achieves more than two orders of magnitude reduction in model size, inference time, and energy consumption. We also demonstrate the trade-off between accuracy and robustness to noise and provide Pareto front solutions as a design parameter in our hypervector design.