1/f noise is main factor to restrict detection ability of magneto-resistive（ MR） sensors at low frequency.And magnetic line of force modulation based on micro-electro-mechanical systems（ MEMS） can reduce 1/f noise above two orders. However

nonlinear response caused by magnetic hysteresis is the main problem to restrict its application

as well as unidirectional response property problem. A bi-direction pulse magnetization method is proposed which can reduce magnetic hysteresis dramatically and improve linearity of integrated MEMS/GMR sensors. in addition

bipolar magnetic field detection can be achieved by distinguishing the response disparity and pulse magnetization of bi-direction. Experimental results show that the bi-direction pulse magnetization method can realize 91 % reduction of hysteresis and 15. 4 % improvement of sensitivity.