With the development of optics and microelectronics technology, the portable 3D scanner which is regarded as combination of laser technology, computer science and artificial intelligence have been applied widely in the three-dimensional measuring field, the built-in electromagnetic tracking technology has played an important role in the portable scanner. Combined with the coordinate conversion formula and equipment we can get, using experimental method, we designed the built-in electromagnetic tracking system, using experimental tests, our system can work normally and we accomplished the design and analysis work. This paper is the introduction of this part.