System and method for reuse of communications spectrum for fixed and mobile applications with efficient method to mitigate interference

A waveform specifically for use in combination with NTSC analog TV signals consisting of multiple CW waveforms or combinations of narrowband waveforms with energy in certain frequency zones within the NTSC six MHz channel width and minimal energy at other frequencies in the channel.

A method for a network of secondary communication devices to share the analog TV spectrum consisting of the steps of,

• each secondary transceivers and secondary base stations measuring the strength of the background TV signal strength, and
• if the primary TV signal strength is greater than a certain level above the noise level but less than another higher level, then
• the secondary system will use a waveform with energy between 1.5 MHz above the channel start frequency and 4.5 MHz above the channel start frequency to avoid interference caused by the analog video and sound carriers.

A system to use the TV spectrum on a secondary basis, comprising:

• of a distributed network of fixed or mobile secondary transceivers that measure the TV signal power levels, and
• a communicate system that sends this information to a central controller, and
• a central controller that thresholds this information to determine which secondary transceivers are located in regions where the primary TV signal is too weak for viewing, thus allowing the secondary transceivers to be able to transmit on this frequency without causing significant interference to the primary TV receivers.