Kneel for the electronics and communication engineering Postgraduate Professional Course Bibliography (which version of the book is used for Huali Signal and System and Digital Signal).
8 14 Signals and Systems (including digital signal processing), Signal and Systems Analysis edited by Zhao Lejun, Signals and Systems edited by Mechanical Industry Press, Zheng and Zheng, Higher Education Press (2nd edition), Gao Xiquan and xidian university Publishing House.