New signal processing techniques for enhanced knock detection in SI engines

Abstract

Standard knock sensor signal processing typically consists of band-pass filtering followed by integration over a specified time/angular window. The resulting knock intensity serves as input to knock detection & correction part of an engine management system (ECU). While this treatment was initially performed by dedicated ICs, it has recently been implemented by ECU software, leading to a digital signal processing approach. In spite of some evident advantages of this approach, the processing method itself had not changed significantly. In this paper, the possibilities of taking better advantage of digital signal processing techniques are discussed and investigations on some possibilities for improving the overall knock detection performance by means of enhancing the signal processing techniques are presented.