Improvement of RTLS Performance Using Recursive RF Active Echo Algorithm

When it comes to indoor Real-Time Location Systems (RTLS) for an Automatic Guided Vehicle (AGV), the most important factor is to minimize the location estimation error. In industrial sites, centimetre-level accuracy is required for the AGV. Since the duration for measuring the position of an AGV is slower than the speed of arriving RF signals, the margin of error inevitably becomes larger than in systems that use low-speed media such as ultrasonic waves. To minimize such errors, a short-range location estimation Recursive RF Active Echo (RRFAE) algorithm is presented. Increasing the time ratio by repeatedly and interactively reflecting the signal can reduce measurement error. That is, there is an effect of expanding the measurement distance by the number of iterations. We propose and implement a precise positioning algorithm in an indoor environment where many reflections exist. The error analysis of the RRFAE algorithm after hardware correction shows that the level of the RRFAE's errors is only one tenth that of an RTLS system that uses other RF signals

Heteroepitaxial Control of Fermi Liquid, Hund Metal, and Mott Insulator Phases in Single-Atomic-Layer Ruthenates

Interfaces between dissimilar correlated oxides can offer devices with versatile functionalities, and great efforts have been made to manipulate interfacial electronic phases. However, realizing such phases is often hampered by the inability to directly access the electronic structure information; most correlated interfacial phenomena appear within a few atomic layers from the interface. Here, atomic-scale epitaxy and photoemission spectroscopy are utilized to realize the interface control of correlated electronic phases in atomic-scale ruthenate-titanate heterostructures. While bulk SrRuO3 is a ferromagnetic metal, the heterointerfaces exclusively generate three distinct correlated phases in the single-atomic-layer limit. The theoretical analysis reveals that atomic-scale structural proximity effects yield Fermi liquid, Hund metal, and Mott insulator phases in the quantum-confined SrRuO3. These results highlight the extensive interfacial tunability of electronic phases, hitherto hidden in the atomically thin correlated heterostructure. Moreover, this experimental platform suggests a way to control interfacial electronic phases of various correlated materials.11Nsciescopu