Analysis of magnetic disturbance due to buildings

Abstract

In the National Space Development Agency of Japan (NASDA), a nonmagnetic space is required in the Spacecraft Magnetic Test Site (SMTS) to measure mainly magnetic moments of spacecrafts. This is realized by means of the main coil of a three-axis Braunbek system combined with a nonmagnetic noise source space (NMNSS) of which the radius from SMTS is more than 300 m. A magnetically shielded room was not installed. Direct-current (dc) magnetic disturbance due to buildings in the earth magnetic field and alternating-current (ac) disturbances due to human activities can decay sufficiently in such a large space. This paper describes dc magnetic disturbance due to a tall building, which is planned inside NMNSS. First, a method of analysis for three-dimensional magnetic field computation was verified by investigating the distribution of magnetic disturbance due to buildings of steel and concrete structure, which exist in NASDA. Secondly, magnetic disturbance 1 due to the planned tall building was discussed. It was found that magnetic field concentrates at the core part of the top floor as an inlet and the office part of lower floors as an outlet. Consequently, considerably large 1 with positive value was observed around them and 1 with negative value was widely spread. 1 at SMTS was 60 nT. When the height of the tall building was shortened to half, 1 was reduced by two-thirds. This change may correspond to the difference of total surface area between them.Index Terms-Magnetic disturbance due to a building, magnetic moment, National Space Development Agency of Japan (NASDA), nonmagnetic space, spacecraft, three-dimensional (3-D) magnetic field analysis.

A Monte Carlo Localization algorithm for 2-D indoor self-localization based on magnetic field

“…The framework of buildings we have chosen as experiment environment is made from reinforced concrete and steel, which is supposed to have static and extremely low-frequency magnetic fields [18]. The photo of our experimental environment is shown in Fig.…”

Indoor Space Classification Using Cascaded LSTM

“…It is generated by earth's rotation and the movement of molten iron in the earth's core, which is omnipresent. The GMF generated are not uniform inside the building areas due to materials like iron, steel, concrete, and other equipment [11]. Due to these interference in the GMF inside buildings, it can be used as one of the technologies of location based service (LBS).…”

Algoritmo de paralelización para la estimación en tiempo real del ángulo de guiñada de un UAV

“…En algunos casos se utilizan también magnetómetros, los que proveen de una referencia absoluta del norte magnético. Pero debido a las fluctuaciones de campo magnético en ambientes interiores ocasionadas por estructuras metálicas y dispositivos electrónicos [5], el uso del magnetómetro está aconsejado sólo para exteriores.…”