Research on Ultra-Wideband (UWB) Accurate Positioning under Signal Interference Based on Deep Learning

UWB (Ultra-Wideband) technology is also called "Ultra-Wideband", also known as pulse radio technology. UWB-based positioning technology has real-time indoor and outdoor accurate tracking capabilities, with high positioning accuracy, which can achieve centimeter-level or even millimeter-level positioning. Based on the provided anchor point ranging information, this paper analyzes normal and abnormal data and establishes an accurate positioning model. For task 1, preprocess the data, export the file, delete invalid data, and fill in missing values. For task 2, it is required to establish models for normal and abnormal data respectively. For task 3, it is consistent with the model obtained in task 2. The only difference is that the coordinates of the four anchor points used for the test data have changed. When the target coordinates are calculated, the anchor point coordinates can be replaced to obtain the model required by task 3. For task 4, use the processed data in task one to establish a mathematical model, and train the model through the integrated learning method to determine whether the collected signal is interference. For task 5, first use the integrated learning model in task four to eliminate the interference data in the data, import the eliminated data into the positioning model of task two for positioning, and add Kalman based on interference recognition to the static estimation algorithm.

Heteronuclear and Homonuclear Finite Pulse Radio Frequency Driven Recoupling

Homonuclear finite-pulse radio frequency driven recoupling (fp-RFDR) has been broadly used in multi-dimensional magic-angle spinning (MAS) solid-state NMR experiments over the past 20 years. The theoretical and the simulated descriptions of this method were presented during that time, resulting in an understanding of the influence of chemical shift offset, finite pulse effects, and dipolar truncation. Here we present an operator analysis of both heteronuclear and homonuclear fp-RFDR. By numerical simulation, we show which operators are involved in the longitudinal exchange for both heteronuclear and the well-known homonuclear sequences. This results in a better understanding of the influence of phase cycling of the fp-RFDR pulses, which is typically a variant of XY cycling. We investigate the heteronuclear and homonuclear fp-RFDR signals and evolution of the operators through the fp-RFDR block. We show the convergence of the evolutions of the heteronuclear and homonuclear fp-RFDR signals at even numbers of rotor periods and completely different evolution between them. We demonstrate heteronuclear 1H- 13C and 1H-15N fp-RFDR magnetization transfer using a microcrystalline SH3 sample at 100 kHz MAS.