INPLANE VECTOR MAGNETOMETER EMPLOYING A SINGLE UNBIASED MAGNETORESISTOR

This paper extends previous work, where a single barber-pole magnetore sistor (MR) was employed for measuring simultaneously two magnetic fie ld components, The present work differs from the previous one in emplo ying a single unbiased MR, which is simpler and less expensive, The pr esent arrangement, Like the previous one, relies on a rotating excitat ion method, A specially devised elliptically rotating field is employe d for this purpose, The latter causes the material magnetization to ro tate uniformly when there is no external field present. The presence o f an external magnetic field is detected by measuring the time shifts of the resulting MR ac output zero-crossings, Despite the similarity b etween the present system and its previous counterpart, the sensitivit ies of detection of the present arrangement are equal for the two orth ogonal components of the externally measured field, It is also interes ting that the intensities of the sinusoidal excitation fields in the p resent case are equal, However, the excitation coils are not perpendic ular to each other as they were in the previous barber-pole case.