  RFID localization is considered the key enabler of automating the process of
inventory tracking and management for high-performance logistic network. A
practical and deployable RFID localization system needs to meet reliability,
throughput, and range requirements. This paper presents RF-Chord, the first
RFID localization system that simultaneously meets all three requirements.
RF-Chord features a one-shot multisine-constructed wideband design that can
process RF signal with a 200 MHz bandwidth in real-time to facilitate one-shot
localization at scale. In addition, multiple SINR enhancement techniques are
designed for range extension. On top of that, a kernel-layer-based near-field
localization framework and a multipath-suppression algorithm are proposed to
reduce the 99% long-tail errors. Our empirical results show that RF-Chord can
localize more than 180 tags 6 m away from a reader within 1 second and with 99%
long-tail error of 0.786 m, achieving a 0% miss reading rate and ~0.01%
cross-reading rate in the warehouse and fresh food delivery store deployment.

Signal Processing