Co-channel transmission of program signals and ancillary signals

A system for transmitting data and a composite video signal in a common communication channel, wherein the composite video signal is transmitted in a frequency band, the system comprising:

• selecting means for selecting a plurality of carriers, wherein each carrier has a correspondingly unique carrier frequency within the frequency band;
• modulating means for redundantly modulating the data onto each of the selected carriers;
• combining means for combining the redundantly modulated carriers with the composite video signal;
• and,
• demodulating means for demodulating the data from the redundantly modulated carriers.

A system for metering tuning of television programs in a sampled household and for monitoring broadcasts of television programs, wherein the television programs are transmitted by way of a television signal, and wherein the television signal has a bandwidth, the system comprising:

• adding means for adding first data to the television signal at a first frequency and for adding second data to the television signal at a second frequency, wherein the first and second frequencies are within the bandwidth of the television signal;
• metering means for metering television tuning by detecting the first data;
• and,
• monitoring means for monitoring broadcasts of television programs by detecting the second data.

An apparatus for non-intrusive measurement of tuning to a broadcast television signal within a sampled household, the apparatus comprising:

• modulating means within the sampled household for modulating a time-varying ancillary code onto a carrier having a carrier frequency within a video bandwidth of the broadcast television signal;
• non-intrusive acquiring means adjacent a display of the television signal for non-intrusively acquiring the modulated carrier;
• and,
• demodulating means for demodulating the time-varying ancillary data from the modulated carrier and for storing the time-varying ancillary data for subsequent transmission to a central office.

An apparatus for non-intrusive measurement of tuning to a broadcast television signal within a sampled household, the apparatus comprising:

• modulating means within the sampled household for modulating a time-varying ancillary code onto a carrier having a carrier frequency within a video bandwidth of the broadcast television signal;
• non-intrusive acquiring means adjacent a display of the television signal for non-intrusively acquiring the modulated carrier, wherein the non-intrusive acquiring means comprises a video probe;
• and,
• demodulating means for demodulating the time-varying ancillary data from the modulated carrier and for storing the time-varying ancillary data for subsequent transmission to a central office.

An apparatus for non-intrusive measurement of tuning to a broadcast television signal within a sampled household, the apparatus comprising:

• modulating means within the sampled household for modulating a time-varying ancillary code onto a carrier having a carrier frequency within a video bandwidth of the broadcast television signal;
• non-intrusive acquiring means adjacent a display of the television signal for non-intrusively acquiring the modulated carrier, wherein the non-intrusive acquiring means comprises an intermediate frequency probe;
• and,
• demodulating means for demodulating the time-varying ancillary data from the modulated carrier and for storing the time-varying ancillary data for subsequent transmission to a central office.