Progress of the National Data Broadcasting standard

Abstract

A National Data Broadcasting Committee (NDBC) has been formed in 1993 to develop a standard for broadcasting high speed digital data together with standard NTSC transmissions. These signals should not affect standard NTSC receivers but can be received and decoded by specially designed receivers. The NDBC received five proposals and two proponents submitted hardware for testing. The other proposals were withdrawn. The two systems which were tested were not similar in implementation and performance but generally demonstrated the capability of transmitting digital data together with the NTSC signal.