How to simulate magnetometer used on navigation system?
The unit does not really matter if you measure the right quantity. But obviously angle magnetic induction and angle are different quantities. Typically—but it might depends on the type of magnetometer used and is not true e.g. of mechanical compass—there will be two or three magnetometers detecting components of the magnetic induction vector, and then you calculate the bearing to magnetic north, and if you have three components the inclination from those.
The raw output of an electric vector magnetometer, measuring one axis of the magnetic induction vector, will be a voltage. You can convert it to the inductance in μT or whatever unit, but for navigation you only care about the direction and the units cancel out when you calculate that so you don't have to.
For magnetometers intended for nagivation, the required accuracy is only specified for the angle, in degrees, because the magnitude is not used.