Magnetic stripe card reader
View Patent ↗A magnetic stripe card reader useful for reading magnetic stripe bearing cards having at least one magnetic track, the magnetic stripe reader including a magnetic stripe reader head including multiple magnetic sensors including at least one magnetic track reading sensor for reading data encoded in a magnetic track of a magnetic stripe and at least one magnetic sensor which does not read encoded data, the magnetic stripe reader head providing magnetic sensor outputs including at least one magnetic track sensor reading output and at least one magnetic sensor output which has no encoded data therein and a subtractor operative to subtract at least a portion of the at least one magnetic sensor output, which has no encoded data therein, from the at least one magnetic track sensor reading output having card data encoded thereon, thereby to cancel interference from the at least one magnetic track reading output.
1. A magnetic stripe card reader useful for reading magnetic stripe bearing cards having at least one magnetic track, said magnetic stripe reader comprising:
a magnetic stripe reader head comprising multiple magnetic sensors including at least one magnetic track reading sensor for reading data encoded in a magnetic track of a magnetic stripe and at least one magnetic sensor which does not read encoded data, said magnetic stripe reader head providing magnetic sensor outputs including at least one magnetic track sensor reading output and at least one magnetic sensor output which has no encoded data therein; and
a subtractor operative to subtract at least a portion of said at least one magnetic sensor output, which has no encoded data therein, from said at least one magnetic track sensor reading output having card data encoded thereon, thereby to cancel interference from said at least one magnetic track reading output.
2. A magnetic stripe card reader according to claim 1 and wherein said magnetic sensor output, which has no encoded data thereon, is produced by reading a location on said magnetic stripe bearing card which corresponds to a location where a third track could have been encoded on the stripe.
3. A magnetic stripe card reader according to claim 1 and wherein said magnetic sensor output, which has no encoded data thereon, is produced by reading a location on said magnetic stripe bearing card which corresponds to a location where a fourth track could have been encoded on the stripe.
4. A magnetic stripe card reader according to claim 1 and wherein said at least one magnetic sensor which does not read encoded data forms part of said magnetic stripe reader head.
5. A magnetic stripe card reader according to claim 1 and wherein said at least one magnetic sensor which does not read encoded data does not form part of said magnetic stripe reader head.
6. A magnetic stripe card reader according to claim 1 and wherein said subtractor provides an interference adjusted output to a processor which is not part of said magnetic stripe card reader.
7. A magnetic stripe card reader according to claim 1 and also comprising a processor and wherein said subtractor provides an interference adjusted output to said processor.
8. A point of sale device comprising:
a housing;
a processor; and
a magnetic stripe card reader useful for reading magnetic stripe bearing cards having at least one magnetic track, said magnetic stripe reader comprising:
a magnetic stripe reader head comprising multiple magnetic sensors including at least one magnetic track reading sensor for reading data encoded in a magnetic track of a magnetic stripe and at least one magnetic sensor which does not read encoded data, said magnetic stripe reader head providing magnetic sensor outputs including at least one magnetic track sensor reading output and at least one magnetic sensor output which has no encoded data therein; and
a subtractor operative to subtract at least a portion of said at least one magnetic sensor output, which has no encoded data therein, from said at least one magnetic track sensor reading output having card data encoded thereon, thereby to cancel interference from said at least one magnetic track reading output and to provide an interference adjusted output to said processor.
9. A point of sale device according to claim 8 and wherein said magnetic sensor output, which has no encoded data thereon, is produced by reading a location on said magnetic stripe bearing card which corresponds to a location where a third track could have been encoded on the stripe.
10. A point of sale device according to claim 8 and wherein said magnetic sensor output, which has no encoded data thereon, is produced by reading a location on said magnetic stripe bearing card which corresponds to a location where a fourth track could have been encoded on the stripe.
11. A point of sale device according to claim 8 and wherein said at least one magnetic sensor which does not read encoded data forms part of said magnetic stripe reader head.
12. A point of sale device according to claim 8 and wherein said at least one magnetic sensor which does not read encoded data does not form part of said magnetic stripe reader head.
13. A point of sale device comprising:
a housing; and
a magnetic stripe card reader useful for reading magnetic stripe bearing cards having at least one magnetic track, said magnetic stripe reader comprising:
a processor;
a magnetic stripe reader head comprising multiple magnetic sensors including at least one magnetic track reading sensor for reading data encoded in a magnetic track of a magnetic stripe and at least one magnetic sensor which does not read encoded data, said magnetic stripe reader head providing magnetic sensor outputs including at least one magnetic track sensor reading output and at least one magnetic sensor output which has no encoded data therein; and
a subtractor operative to subtract at least a portion of said at least one magnetic sensor output, which has no encoded data therein, from said at least one magnetic track sensor reading output having card data encoded thereon, thereby to cancel interference from said at least one magnetic track reading output and to provide an interference adjusted output to said processor.
14. A point of sale device according to claim 13 and wherein said magnetic sensor output, which has no encoded data thereon, is produced by reading a location on said magnetic stripe bearing card which corresponds to a location where a third track could have been encoded on the stripe.
15. A point of sale device according to claim 13 and wherein said magnetic sensor output, which has no encoded data thereon, is produced by reading a location on said magnetic stripe bearing card which corresponds to a location where a fourth track could have been encoded on the stripe.
16. A point of sale device according to claim 13 and wherein said at least one magnetic sensor which does not read encoded data forms part of said magnetic stripe reader head.
17. A point of sale device according to claim 13 and wherein said at least one magnetic sensor which does not read encoded data does not form part of said magnetic stripe reader head.