Patent ID: 8406338

Claim:
Improved transmitter apparatus for transmitting an 8VSB digital television signal modulated in accordance with successive eight-level symbols, said 8VSB digital television signal employing 12-phase 2/3 trellis coding that functions as inner convolutional coding for concatenated convolutionally coded portions of said 8VSB digital television signal designed to be received usefully by receivers apt to be in motion such as mobile or hand-held types collectively referred to as “M/H receivers”, successive bytes of said concatenated convolutionally coded portions of said 8VSB digital television signal having outer convolutional coding and being arranged in M/H Groups, successive ones of said M/H Groups being spaced apart from each other by strings of bytes without outer convolutional coding, wherein each of said M/H Groups respectively includes a respective signaling sequence of 8VSB symbols and respective first through fifth training sequences of 8VSB symbols of prescribed values thereafter, wherein said improved transmitter apparatus comprises: an encoder for said 12-phase 2/3 trellis coding that functions as inner convolutional coding for concatenated convolutionally coded portions of said 8VSB digital television signal; at least one encoder for said outer convolutional coding; trellis-initialization apparatus operable for forcing respective sets of consecutive trellis-reset symbols just before said signaling sequences, just before first training sequences, just before said second training sequences, just before said third training sequences, just before said fourth training sequences, and just before said fifth training sequences to have values that cause subsequent 12-phase 2/3 trellis coding by said encoder for said 12-phase 2/3 trellis coding to continue from standardized 2/3 trellis coding states for all said M/H Groups; and an improvement comprising: said trellis-initialization apparatus further operable for forcing respective sets of twenty-four symbols close to the beginning of each one of said M/H Groups to have values that cause subsequent 12-phase 2/3 trellis coding by said encoder for said 12-phase 2/3 trellis coding to continue from standardized 2/3 trellis coding states common to all said M/H Groups.