digital speech communications การใช้

Directly digitizing of speech signals needs too much high bit rate in digital speech communication , thus compression and coding of the speech signals is essential in the process to increase the efficiency of transmission and storage , as well as the channel capacity
Digital speech technology has been widely used in many fields of communications in recent years , but it is just at beginning to use acoustical wave to implement underwater digital speech communications , which mainly results from the bandwidth - limited underwater acoustic communications channel and its high temporal and spatial variability