VSB modem subsystem design for Grand Alliance digital television receivers

The functions of the vestigial sideband modem for the Grand Alliance digital TV are described. The partitioning of these functions is discussed in terms of the prototype hardware and possible future development. The VSB modem subsystem (tuner/demodulator) includes the functions of RF selection, local oscillator, and conversion; IF amplification and band shaping; baseband demodulation; AGC; co-channel filtering; synchronization and phase tracking of the carrier, the bit clock, and the data framing; equalization (ghost cancellation); forward error correction (trellis and RS codes); and data de-interleaving. The interaction and partitioning of these functions is discussed. >