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Azimuth Calculation Basics

Azimuth Calculation Basics - Calculating from the horizontal component of the earth's magnetic field

 

In a real compass (compass needle), the needle follows the earth's magnetic field over the base plate and points to magnetic north.

 

Compared to this, the 2-axis electric compass measures the x and y axes' magnetic fields of the horizontal components of earth's magnetic field, and then calculates the magnetic field's direction θ using the following equation.

 

 θ = arctan (Y-axis value of the earth's magnetic field / X-axis value of the earth's magnetic field)

 

To convert this calculated value to the Azimuth angle (with north as the origin point of 0 degrees and proceeding clockwise), convert using the following equation.

 

 Azimuth = 90° - θ

 

If the standard magnetic field can be measured, the azimuth can be found by use of the above two equations alone.