In-band on-channel digital broadcasting

Claim 3

The method of claim 1 where the step of combining comprises summing.

Claim 4

The method of claim 1 where the step of producing, from each subchannel matched filter output signal and the reference sampler matched filter output signal, a subchannel polarity signal, comprises multiplying each subchannel matched filter output signal by the reference sampler matched filter output signal.

Claim 5

The method of claim 1 where the step of producing, from each subchannel polarity signal, a subchannel output signal, comprises integrating each subchannel polarity signal.

Claim 6

Apparatus for measuring and diminishing the adverse effects of spurious signals in a communications channel, comprising: a data subchannel waveform generator that generates a plurality of data subchannel waveforms, wherein each data subchannel waveform is centered at a corresponding distinct frequency and has a first spectral width, each data subchannel waveform carrying a modulation symbol during a baud interval; a reference waveform generator that generates a reference waveform having a second spectral width which overlaps all the data subchannel waveforms, said reference waveform carrying a reference symbol during said baud interval; a combiner that combines the data subchannel waveforms with the reference waveform to produce a channelized data transmitted reference signal; a transmission system that transmits the channelized data transmitted reference signal through the communications channel; a receiving system that receives the channelized data transmitted reference signal and generating a plurality of subchannel baseband signals and a reference sampler signal therefrom; a matched filter system that generates from said subchannel baseband signals corresponding subchannel matched filter output signals; a reference recovery system that generates from said reference sampler signal a reference sampler matched filter output signal; a sampling system that produces from each subchannel matched filter output signal and the reference sampler matched filter output signal, a subchannel output signal.

Claim 7

Apparatus for measuring and diminishing the adverse effects of spurious signals in a communications channel, comprising: a data subchannel waveform generator that generates a plurality of data subchannel waveforms, wherein each data subchannel waveform is centered at a corresponding distinct frequency and has a first spectral width, each data subchannel waveform carrying a modulation symbol during a baud interval; a reference waveform generator that generates a reference waveform having a second spectral width which overlaps all the data subchannel waveforms, said reference waveform carrying a reference symbol during said baud interval; a combiner that combines the data subchannel waveforms with the reference waveform to produce a channelized data transmitted reference signal; a transmission system that transmits the channelized data transmitted reference signal through the communications channel; a receiving system that receives the channelized data transmitted reference signal and generating a plurality of subchannel baseband signals and a reference sampler signal therefrom; a matched filter system that generates from said subchannel baseband signals corresponding subchannel matched filter output signals; a reference recovery system that generates from said reference sampler signal a reference sampler matched filter output signal; a sampling system that produces from each subchannel matched filter output signal and the reference sampler matched filter output signal, a subchannel output signal.

Claim 8

The apparatus of claim 5 where the combiner comprises a summer.

Claim 9

The apparatus of claim 5 where the sampling system comprises a multiplier bank multiplying each subchannel matched filter output signal by the reference sampler matched filter output signal.

Claim 10

The apparatus of claim 5 where the sampling system comprises an integrator bank integrating each subchannel polarity signal.