Patent ID: 7292286

Claim:
An apparatus for modulating both quadrature components of each of a plurality of RF signals with waveforms comprising time varying vectors uniquely associated with each of the RF signals, the RF signals together comprising a multichannel signal spanning a frequency range that is substantially centered about a center frequency F, said apparatus comprising: means for generating a CW signal having a frequency equal to the center frequency F; means for producing digital representations of a first composite baseband signal and a second composite baseband signal, wherein: the first and second composite baseband signals each comprise at least one sinusoid that is modulated in quadrature with waveforms that are each a linear combination of the waveforms comprising the time varying vector that is uniquely associated with at least one of the RF signals having a frequency higher than F and the waveforms comprising the time varying vector that is uniquely associated with at least one of the RF signals having a frequency lower than F; and wherein each of the first and the second composite baseband signals has a baseband frequency span that is substantially half of the frequency range spanned by the multichannel signal; means for converting the digital representations of the first and second composite baseband signals to a first analog and a second analog composite baseband signal respectively; and means for modulating in quadrature the CW signal with the first analog and the second analog composite baseband signals to generate the multichannel signal.