The frequency dispersion effects of the stress wave and external noise result in inaccurate positioning of the pipeline damage. To deal with the above issue the deconvolution method based on wavelet estimation is adopted to process the experimental data of the guided wave. The numerical simulation and experimental results have shown that this method can suppress the frequency dispersion of the guided wave effectively and improve the positioning accuracy in the pipeline damage detection. As a single exciter has limited energy and the measured signal has a lower signal-to-noise ratio, the coded excitation technique is applied. Two signals with different coding methods are designed and then used in a longitudinal wave propagation model of the pipeline .The numerical results have demonstrated that the coded excitation technique can improve the capability of anti interference and resolution in the pipeline damage detection.