Annex D - RF/Transmission System
Annex D describes the physical layer (VSB transmission system) of the ATSC system for terrestrial and high data rate cable applications. As such, it does not put direct constraints on MPEG 2 beyond the maximum data rate it is capable of carrying.
The VSB system can carry (in a 6 MHz channel) 4.5/286x684/832 x10e6 = 12935.38.... MPEG packets per second in the 8T-VSB terrestrial mode, and twice that rate in the 16-VSB high data rate (cable) mode.