With the approaching adoption of digital compression and the supporting development of transport systems to effect the delivery of all digital television, there is intense activity surrounding the search for low cost but high performance modems for digital signals. This paper discusses recent advances in the state-of-the-art of modulator/demodulator technology for the satellite channel. An all-digital modem implementation is described, yielding benefits of near-theoretical performance, low cost, high reliability and variable rate operation from 1 to 60Mbps.