I am trying to carry up to 8 channels of audio (10k bandwidth) over 2 wires of length 1.2km.
The idea I have is to ADC all the audio and then use a frequency synthesizer (AD9959 or similar) to apply FSK modulation to each then transmit
it over the 2wires. Basically each of the audio channels will have its own carrier. The problem I can't seem to work out is how do you added all the
carriers together and transmit it over 2wires, I assume you can only transmit one carrier at a time or if you have a better way of transmitting these audio over 2wire please let me know.
Just to add that the 8 audio channels are independent so if they are combined (added) for easy 2 wire transmission they need to be properly separated at the other end.
Thanks in advance