Sums: Sniffing Unknown Multiband Signals under Low Sampling Rates

TL;DR

Sums is a system that combines hardware and deep learning to efficiently analyze multiband wireless signals at low sampling rates, enabling cost-effective spectrum sensing and protocol recognition.

Contribution

It introduces a hardware-algorithm co-designed system that performs blind multiband signal analysis using sub-Nyquist sampling and multi-task deep learning.

Findings

Achieves higher accuracy than state-of-the-art in spectrum sensing.

Effectively performs modulation classification and demodulation.

Operates with only 50 MSPS sampling rate for GHz bandwidth.

Abstract

Due to sophisticated deployments of all kinds of wireless networks (e.g., 5G, Wi-Fi, Bluetooth, LEO satellite, etc.), multiband signals distribute in a large bandwidth (e.g., from 70 MHz to 8 GHz). Consequently, for network monitoring and spectrum sharing applications, a sniffer for extracting physical layer information, such as structure of packet, with low sampling rate (especially, sub-Nyquist sampling) can significantly improve their cost- and energy-efficiency. However, to achieve a multiband signals sniffer is really a challenge. To this end, we propose Sums, a system that can sniff and analyze multiband signals in a blind manner. Our Sums takes advantage of hardware and algorithm co-design, multi-coset sub-Nyquist sampling hardware, and a multi-task deep learning framework. The hardware component breaks the Nyquist rule to sample GHz bandwidth, but only pays for a 50 MSPS sampling rate. Our multi-task learning framework directly tackles the sampling data to perform spectrum sensing, physical layer protocol recognition, and demodulation for deep inspection from multiband signals. Extensive experiments demonstrate that Sums achieves higher accuracy than the state-of-theart baselines in spectrum sensing, modulation classification, and demodulation. As a result, our Sums can help researchers and end-users to diagnose or troubleshoot their problems of wireless infrastructures deployments in practice.