信号举例( 1) 声音 Represent air pressure as a function of time at a point in space “I like digital signal processing” Time.sec. 2017/10/11 数字信号处理 6信号举例 （1） 声音 - R t epresent air pressure as a f ti f unction of time at a point in space “I like digital signal p g rocessing” 2017/10/11 数字信号处理 6