Measuring peak and average power of digitally modulated advanced television systems

The author reviews why it is that the peak power of the NTSC visual signal is measured, noting that its average power varies inversely with scene brightness. The average power of a digital TV signal is independent of scene content, motion, and other variables and is, therefore, the parameter to be measured and used to compute interference, coverage, and the utility cost to provide that coverage. Transient peak power varies with the data stream, and for this reason it is a statistical quantity. A method to determine the transient peak power is described. Thermocouple power sensors and the limitations of square law power sensors are also discussed