Convert Digital Signals to Analog Signals Steps
Step 1 Decompression:
If the voice signal was compressed by the sender, it is first decompressed.
Step 2 Decoding:
The received, binary formatted voice samples are decoded to the amplitude value of the samples. This information is used to rebuild a PAM signal of the original amplitude.
Step 3 Reconstruction of the analog signal:
The PAM signal is passed through a properly designed filter that reconstructs the original analog wave form from its digitally coded counterpart. The whole process is simply the reverse of the analog-to-digital conversion. Like analog-to-digital conversion, digital-to-analog conversion is performed by DSPs, which are located on the voice interface cards. The conversion is needed for calls being received from a packet network or digital interfaces, which are then transmitted out an analog voice interface.
If the voice signal was compressed by the sender, it is first decompressed.
Step 2 Decoding:
The received, binary formatted voice samples are decoded to the amplitude value of the samples. This information is used to rebuild a PAM signal of the original amplitude.
Step 3 Reconstruction of the analog signal:
The PAM signal is passed through a properly designed filter that reconstructs the original analog wave form from its digitally coded counterpart. The whole process is simply the reverse of the analog-to-digital conversion. Like analog-to-digital conversion, digital-to-analog conversion is performed by DSPs, which are located on the voice interface cards. The conversion is needed for calls being received from a packet network or digital interfaces, which are then transmitted out an analog voice interface.
Comments