# Physical–MAC Layer Integration: A Cross-Layer Sensing Method for Mobile UHF RFID Robot Reading States Based on MLR-OLS and Random Forest

## TL;DR

This paper introduces a new method for RFID robots to better sense and read goods in warehouses by combining physical and MAC layer data, improving accuracy and efficiency.

## Contribution

The novel contribution is a cross-layer sensing method using MLR-OLS and random forest to enhance RFID robot performance in shelf and goods state sensing.

## Key findings

- The proposed method achieves centimeter-level shelf positioning accuracy at medium and low robot speeds.
- The adaptive reading strategy significantly improves the goods read rate by targeting missing items.
- The method reliably estimates goods distribution and missing goods count using physical and MAC layer features.

## Abstract

In automated warehousing scenarios, mobile UHF RFID robots typically operate along preset fixed paths to collect basic information from goods tags. They lack the ability to perceive shelf layouts and goods distribution, leading to problems such as missing reads and low inventory efficiency. To address this issue, this paper proposes a cross-layer sensing method for mobile UHF RFID robot reading states based on multiple linear regression-orthogonal least squares (MLR-OLS) and random forest. For shelf state sensing, a position sensing model is constructed based on the physical layer, and MLR-OLS is used to estimate shelf positions and interaction time. For good state sensing, combining physical layer and MAC layer features, a K-means-based tag density classification method and a missing tag count estimation algorithm based on frame states and random forest are proposed to realize the estimation of goods distribution and the number of missing goods. On this basis, according to the read state sensing results, this paper further proposes an adaptive reading strategy for RFID robots to perform targeted reading on missing goods. Experimental results show that when the robot is moving at medium and low speeds, the proposed method can achieve centimeter-level shelf positioning accuracy and exhibit high reliability in goods distribution sensing and missing goods count estimation, and the adaptive reading strategy can significantly improve the goods read rate. This paper realizes cross-layer sensing and read optimization of the RFID robot system, providing a theoretical basis and technical route for the application of mobile UHF RFID robot systems.