×

Double-sided rapid drift correction

  • US 8,571,811 B1
  • Filed: 01/22/2010
  • Issued: 10/29/2013
  • Est. Priority Date: 01/22/2010
  • Status: Active Grant
First Claim
Patent Images

1. A method of compensating for sensor drift in an environmental gas sensor, the method comprising:

  • maintaining in a computer memory a representation of a background gas concentration range for a gas sensor, the background gas concentration range existing between a minimum sensor reading low value and a minimum sensor reading high value, the minimum sensor reading low value corresponding to a first gas concentration value and the minimum sensor reading high value corresponding to a second gas concentration value, higher than the first gas concentration value;

    maintaining in the computer memory criteria for declaring patterns in background gas concentration readings based on the background gas concentration range;

    accepting recurring gas concentration readings from the gas sensor;

    analyzing the recurring gas concentration readings against the maintained criteria with a processor coupled to the computer memory, wherein analyzing comprises determining whether the concentration readings indicate the presence of a pattern of background gas concentration readings either lower than the minimum sensor low value or greater than the minimum sensor reading high value;

    when analysis of the recurring gas concentration readings indicates the presence of a pattern of background gas concentration readings lower than the minimum sensor reading low value, adjusting an indicated gas concentration upwards; and

    when analysis of the recurring gas concentration readings indicate the presence of a pattern of background gas concentration readings greater than the minimum sensor reading high value, adjusting the indicated gas concentration downwards.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×