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本文为消除发动机缸内气体压力测量中的通道效应的影响提出了一种新的方法——小波变换法。小波变换能针对气体压力信号的时变和非线性特征，充分反映出发动机气缸压力信号突变点附近的频变特性。分析中利用３次Ｂ样条小波对４１３５柴油机的气体压力信号按Ｍａｌａｔ算法进行分解，分离出了气体压力信号中的通道效应，并利用采用反对称小波时，信号奇异点与其小波变换模极大值对过零点的关系，对压力急升点进行了定位，最后运用小波的滤波性能去除通道效应的干扰后，对压力信号进行了重构。
In this paper, a new method, wavelet transform, is proposed to eliminate the influence of channel effect on gas pressure measurement in engine cylinder. The wavelet transform can reflect the time-varying and nonlinear characteristics of the gas pressure signals and fully reflects the frequency-changing characteristics around the sudden change point of the pressure signal of the engine cylinder. In the analysis, the gas pressure signal of 4135 diesel engine is decomposed by Malat algorithm using cubic B-spline wavelet, and the channel effect in gas pressure signal is separated. When the antisymmetric wavelet is used, the signal singular point and its wavelet transform module are extremely large Value of the zero crossing point of the pressure surge point has been positioned, and finally the use of wavelet filtering to remove the channel effect of interference, the pressure signal has been reconstructed.