CNS Core: Small: A New Paradigm of Scalable Acoustic IoT through Distributed On-the-fly Beamforming

This project explores the design and development of acoustic technology as a complementary modality to radio frequency (RF) for indoor smart Internet of Things (IoT) applications. However, today’s widely available smart devices with in-built acoustic interfaces are neither cost-effective nor energy-efficient, while acoustic tags designed for low-power applications have exposed significantly limited performance in one or more dimensions of throughput, range and energy efficiency.

Towards enabling a myriad of practical IoT applications with acoustics, the proposed research explores a novel collaborative paradigm, where it brings together multiple, distributed low-power acoustic tags to enable on-the-fly transmit time-delay beamforming (2D and 3D) to a target receiver, thereby delivering significant performance gains in range, throughput and energy efficiency simultaneously. It can impact our society in multiple ways -- from novel IoT applications to more broadly enabling low-power acoustic communication in a wide array of application domains ranging from secure acoustic spaces to immersive media and underwater sensing.

It aims to inform relevant wireless and acoustic professional organizations by demonstrating the potential of such an energy-efficient distributed acoustic paradigm. It will also impact the audio industry that is actively working on speaker arrays for targeted, immersive audio in numerous consumer applications.

The proposed research aims to take an important step towards this vision by addressing three key challenges: (i) scalability -- enabling an on-demand beamforming array that can implicitly synchronize and share data amongst a distributed set of tags and scale its performance with the array size over a wideband; (ii) coexistence -- enabling such wideband performance without causing or being impacted by audible interference created in the process; and (iii) multiple access -- efficiently allowing multiple tags to access the channel in creating practical IoT applications that often include both near and far-field deployments. Through the design of an analytically-sound collaborative beamforming framework, a novel distributed acoustic tag-array is proposed that brings together multiple low-power individual tags on-demand through intelligent distributed mechanisms for time-delay (2D and 3D) beamforming and angle-dependent signal whitening.

The latter enable wideband operations in both near and far-field, while suppressing interference to unwanted regions and allowing multiple such tag-arrays to coexist. The proposed paradigm is expected to be implemented and tested rigorously in real world, while enabling two practical acoustic IoT applications in inventory management and targeted audio delivery.

The project paves the way for future IoT systems to leverage acoustic interfaces with scalable performance as a complementary modality to RF.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.