Programmable signal path system for magnetic tracking devices for local navigation tasks

Abstract

Introduction. The article is dealing with the Magnetic Tracking signal path for measurement of objects’ positions in nearby places. The basic principle of the Magnetic Tracking method is based on measurement of magnetic induction of the reference magnetic fields and the calculation of the objects position based on it.Problem analysis. Big advantages of magnetic tracking technologies are the non-line-of-sight feature compared to optical tracking and high accuracy of long time measurement compared to inertial tracking. However, a very large signal range and significant distortions due to nearby metallic objects are serious drawbacks preventing magnetic tracking from being widely used.Selection and configuration of signal path components. Taking into account the requirements of uptoday microelectronics, in particular for the sensors of the Internet of Things, the signal path of the Magnetic Tracking sensors is implemented on the concept of System on Chip. Basic components of the signal path are software Programmable Waveform Generator, Programmable Gain Amplifiers and Programmable Mixer. Configurations of the components are provided by Application Programming Interface routines.                                                                                                                                                                                                                                                                                                                                               Functional and model studies of the synchronous detector. Noise immune processing is based on synchronous detector. SPICE simulations and analysis of this detector are provided.Implementation of signal path of magnetic tracking. The signal converter has been implemented on the Programmable System on Chip PSoC 5LP (Cypress Semiconductor). The module CY8CKIT-059 Prototyping Kit has been used. The developed software for controlling the measurement process provides controlling the conversion mode, dynamic amplification switching, analog-to-digit converting, etc.Conclusions. The novelty of the solutions presented in the work is the combination of signal amplification dynamic switching and the noise immune processing. Reference magnetic fields are formed by actuator coils in the lowfrequency spectrum of electromagnetic waves. Signals are produced by sensor coils and are used for objects position calculation. Technologies of Magnetic Tracking are considered as high promising solutions for Virtual Reality, Augmented Reality and Internet of Things.