Patent ID: 6246233
Filing Date: 2001-06-12
Classification: G01D,G01P

Abstract:
A frequency doubling sensor array to detect the motion of a magnetic pattern generated by a moving magnetic source magnetized at a pitch .lambda., comprising:a first pair of sensor elements separated by 21/2.lambda. and connected to form a first half-bridge;a second pair of sensor elements separated by 21/2.lambda. and connected to form a second half-bridge, the first sensor element of the first and second pairs being separated by 3.lambda./8;a third pair of sensor elements separated by 21/2.lambda. and connected to form a third half-bridge, the first sensor element of the third pair being separated by 3.lambda./8 from the first sensor element in the second pair and by 3.lambda./4 from the first sensor element in the first pair;a fourth pair of sensor elements separated by 21/2.lambda. and connected to form a fourth half-bridge, the first sensor element of the fourth pair separated by 3.lambda./8 from the first sensor element in the third pair and by 3.lambda./4 from the first sensor element in the second pair; andplural complementary sensor elements, each complementary sensor element separated by .lambda. from and connected to a corresponding sensor element of the first through fourth pairs of sensor elements.