METHOD FOR SUPPRESSING PHASE NOISE OF HIGH FREQUENCY CARRIER TYPE MAGNETIC FIELD SENSOR AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a method for suppressing a phase noise of a high frequency carrier type magnetic field sensor and an apparatus therefor which enable detecting minute signals to a level of thermal fluctuation of a sensor element itself or thermal noise by reducing an SSB phase noise.;SOLUTION: There are provided a signal generator 1, a first divider 2 connected to the signal generator 1, the sensor element 3 connected to the first divider 2, a series connection circuit which is connected in parallel to the sensor element 3 and is comprised of an attenuator 4 connected to the first divider 2 and a phase shifter 5, a second divider 6 connected to the sensor element 3 and the phase shifter 5, a preamplifier 7 connected to the second divider 6, and a spectrum analyzer 8 connected to the preamplifier 7. A carrier voltage is divided by the first divider 2 and adjusted with the use of the attenuator 4 and the phase shifter 5 so that an output signal of the phase shifter 5 becomes equal in amplitude and different by approximately 180° in phase to a carrier component as an output signal of the sensor element 3.;COPYRIGHT: (C)2002,JPO