Patent attributes
An engine emissions control system is provided. The system may include an exhaust producing engine and an exhaust system through which the exhaust produced by the engine may flow. The system may also include a NOx sensor configured to take a NOx measurement of the amount of NOx in the exhaust produced by the engine. The system may further include a charge density sensing system configured to measure the charge density of a combustion mixture of the engine. In addition, the system may include a controller configured to receive information related to the measurement of the amount of NOx. The controller may be further configured to control a charge density of the combustion mixture with which the engine operates based on the NOx measurement and the charge density measured by the charge density sensing system.