A 1GHz digital channel multiplexer for satellite OutDoor Unit based on a 65nm CMOS transceiver

Satellite digital TV broadcast reception today requires a multiple low-noise block (multi-LNB) head on the dish, as well as a multi-tuner set-top box (STB). Connecting multiple outdoor units (ODU) to the set-top boxes traditionally needed multiple cables. A first step has been achieved with so-called satellite channel stacking switch^TM technology (CSS), able to deliver the full suite of TV programs to all STBs in a single home through a reduced number of cables. However, this pure analog/RF technology does not offer enough flexibility in terms of the number of simultaneous users (12 users maximum) and requires multiple external components like SAW filters, increasing significantly the cost of the solution. Introducing digital processing in this RF dominated application to sort and assemble user channels removes the need of in-band SAW filters, offers full flexibility of channel selection, and supports up to 50 users simultaneously. This digital channel multiplexer (DCM) solution is a transceiver located in the ODU. It receives the satellite signal from the LNB after down conversion to an intermediate frequency (IF), and transmits the channels selected by the users on a single cable to multiple STBs. Each user has some reserved bandwidth on the output signal. The visualisation of the chips, the functions and the block diagram of DCM are also illustrated.