Knocking detection apparatus and internal combustion engine control apparatus

A knocking detection apparatus for detecting knocking of an internal combustion engine, comprising:

• a vibration sensor which detects vibration of the internal combustion engine;
• a frequency analyzer which extracts two or more frequency components from the vibration detected by the vibration sensor;
• a smoothing device which calculates background levels of the vibration of the internal combustion engine by smoothing the frequency components;
• a background level estimator which acquires estimated values of the background level of the internal combustion engine based on an operating state of the internal combustion engine;
• an index calculator which calculates a knocking index indicating whether knocking of the internal combustion engine has occurred by using the frequency components, the background levels, and the estimated values;
• and
• a determination device which determines whether knocking of the internal combustion engine has occurred by comparing the knocking index and a determination threshold.