Looking for a very low cost 2 way communication (transmits and receives simultaneously).
Speed: 1kbps minimum
Channels: Have to support at least 2 channels
What you need to deliver are: the solution theory (can be discrete or chip solution), schematic (in the case of discrete solution), datasheet, and vendor.
The quantity scope: 1,000/10,000 pair of transmit and receive
We will be looking for the solution that has the lowest BOM and manufacture cost per pair of transmit and receive, not the labor cost. If you have multiple solutions, it is a plus.