Jeffery Hamilton

US Patent:

20040028076, Feb 12, 2004

Filed:

Jun 6, 2003

Appl. No.:

10/312931

Inventors:

Christopher Strolle - Ft Washington PA, US
Jeffery Hamilton - Doylestown PA, US
Haosong Fu - Levittown PA, US
Troy Schaffer - Newtown PA, US

International Classification:

H04L012/56

US Classification:

370/466000

Abstract:

A robust data extension is added to a standard 8VSB digital television transmission system by encoding high priority data packets in a rate 1/2 trellis encoder. The high priority data 1/2 trellis encoded packets are multiplexed with normal data packets and input into the normal data service of an 8VSB system, which further contains a rate 2/3 trellis encoder. The combined trellis encoding results in a rate 1/3 trellis encoding for robust data packets and a rite 2/3 trellis encoding for normal packets. Rate 1/3 trellis encoding provides the substantially equivalent robustness of a 2VSB signal while retaining the backward compatibility characteristics or an 8VSB signal. Four legacy requirements for backward compatibility with existing ATSC compliant receivers and transmitters are met: 1) the modulus of the symbol set for robust data transmission is the same as that for an 8VSB signal; 2) compatibility with existing trellis encoders and decoders is maintained; 3) Reed Solomon parity bytes are transmitted as normal data so that existing receivers do not flag robust data packets as having Reed Solomon parity errors; and 4) MPEG compatibility is maintained by guaranteeing that robust data packets will not appear as false MPEG packets that otherwise could destabilize the existing MPEG decoder.